Caltech: The Mechanical Universe

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Topic review
   

Expand view Topic review: Caltech: The Mechanical Universe

NOVA Universe Revealed: Big Bang

by allynh » Thu Nov 25, 2021 1:52 am

The final program was more Fantasy. The whole series was a great disappointment. I'm not even going to bother buying a copy.

Here's a link if you want to watch and harvest the transcript.

NOVA Universe Revealed: Big Bang
https://www.pbs.org/wgbh/nova/video/nov ... -big-bang/

NOVA Universe Revealed: Black Holes

by allynh » Thu Nov 18, 2021 3:09 am

Okay, episode three was just silly, filled with fantasy, so there is nothing to comment on, but here it is if you want to watch it and harvest the transcript.

NOVA Universe Revealed: Alien Worlds
https://www.pbs.org/wgbh/nova/video/nov ... en-worlds/

This is episode four, about "Black Holes".

Now here is where things get bizarre. Remember in the first episode they talked about blue giants exploding to spew heavy elements across the sky, and they never mentioned "Black Holes". Now, just three episodes later, they are showing those blue giants calmly collapsing into "Black Holes", they don't show them exploding at all, so where did all the matter come from to make our Sun.

BTW, The whole series has shown how far NOVA has become simply disinformation. Beautiful computer graphics that fool the eye into thinking something is real there.

Read the book, Evil Geniuses by Kurt Andersen to see where the disinformation is coming from.

Follow the money.

NOVA Universe Revealed: Black Holes
https://www.pbs.org/wgbh/nova/video/nov ... ack-holes/
PREMIERES NOVEMBER 17, 2021 AT 7PM ON PBS

Take a seat on the ultimate thrill ride to explore nature’s strangest and most powerful objects. Black holes can reshape entire galaxies, warp the fabric of space and time, and may even be the key to unlocking the ultimate nature of reality. A new generation of high-energy telescopes is bringing these invisible voids to light, showing that “supermassives” millions or billions of times larger than our sun lurk at the center of nearly every galaxy, including our own. But what happens if you stray too close to one? And what lies beyond the black hole’s abyss? If nothing can ever escape it, is that the end of the story? Or could they be a portal to another dimension—or another universe, full of black holes? (Premiered November 17, 2021)

TRANSCRIPT
Universe Revealed: Black Holes

PBS Airdate: November 17, 2021

NARRATOR: Something is hiding in the darkness, invisible objects of unimaginable power that could hold the key to solving the mysteries of space, time and the universe, itself.

SYLVESTER “JIM”JAMES GATES, JR. (Brown University): To me, a black hole is the greatest exhibition of nature’s mysterious powers.

SUGATA KAVIRAJ (University of Hertfordshire): You literally can’t see them, and that’s what makes them extremely mysterious.

NARRATOR: They are bizarre quirks of nature…

REBECCA “BECKY” SMETHURST (University of Oxford): When we’re studying black holes, we’re right on the edge of human knowledge.

NARRATOR: …and yet, they are sculptors of the cosmos…

IMOGEN WHITTAM (University of Oxford): The jets from black holes are so powerful they can affect the whole shape and nature of a galaxy.

NARRATOR: …even shaping our own galaxy, the Milky Way.

DELILAH GATES (Princeton University): We had hints that black holes were at the center of all galaxies, like our own.

NARRATOR: Can we lift the veil…

HAKEEM OLUSEYI (George Mason University): Forget the one-way trip to Mars, I’m going in the black hole.

NARRATOR: …and reveal their secrets?

KIMBERLY ARCAND (Center for Astrophysics | Harvard & Smithsonian): Fermi revealed something completely astonishing and unexpected. We’ve never seen anything like it.

PRIYAMVADA NATARAJAN (Yale University): Finding these little pieces of the puzzle that did not fit is super exciting.

SHEPERD DOELEMAN (Center for Astrophysics | Harvard & Smithsonian): If you really want to understand the deepest questions of the universe, you have to understand black holes.

NARRATOR: Black Holes, right now, on NOVA.

As we gaze out at the Milky Way, our eyes are drawn to the light, hundreds of billions of stars serenely spinning through the cosmos.

IMOGEN WHITTAM: When we look up at the night sky, the stars and planets that we see are beautiful, but actually it’s in the space between these, in the dark patches, that some of the most fascinating things lie.

NARRATOR: In places where there is no light, objects of profound mystery bide their time. Awesome in their simplicity and perfection, we call them “black holes.”

KIRSTEN HALL (Center for Astrophysics | Harvard & Smithsonian): A black hole is an infinitely dense point in space, from which nothing can escape, not even light.

NIAL TANVIR (University of Leicester): It’s extraordinary to think that black holes are everywhere in the universe, that they have existed from very early times in the universe.

NARRATOR: When quiet, they are almost impossible to detect.

URMILA CHADAYAMMURI (Center for Astrophysics | Harvard & Smithsonian): We’re talking about a region of space where, if something falls, then we’ll never know about it, ever again.

NARRATOR: They hold the power to shred stars and worlds, but also, the potential to shape galaxies.

GRANT TREMBLAY (Center for Astrophysics | Harvard & Smithsonian): Black holes are one of the most fundamentally important singular objects that might dictate how galaxies form and evolve.

ANDREW PONTZEN (University College London): It’s natural to fear them, but we’re learning that they’re essential. You can’t live with them, but you also can’t live without them.

NARRATOR: And they may hold the secret to the ultimate fate of the universe.

KIRSTEN HALL: Black holes, on a fundamental level, challenge our understanding of physics, of the way that everything in the universe works.

SHEP DOELEMAN: Black holes are the most mysterious objects in the universe, full stop.

NARRATOR: To understand black holes, we have to start at the beginning, at the moment of birth.

CHIARA MINGARELLI (University of Connecticut and Flatiron Institute): Black holes that are a few times the mass of the sun probably formed from giant stars that were maybe about 20- to 30-times the mass of the sun.

NARRATOR: Enormous stars, burning bright blue with intense heat, but the brightest stars are the shortest lived.

GRANT TREMBLAY: A star is a big ball of gas, there’s outward gravity pushing in. The thing wants to collapse in on itself under its own self-gravity. But the fusion that’s happening within the star’s core liberates so much light that the outward radiation pressure prevents the collapse of that star. But eventually that gives up.

NARRATOR: A star like that can burn through its nuclear fuel in just a few million years. And when its power source runs out, it collapses under its own gravitational pull.

CHIARA MINGARELLI: There’s so much material that’s collapsing during their final few moments that they create this massive dense ball of neutrons that continues to collapse.

NARRATOR: A star 20-times the mass of our sun or larger, crushed by the force of gravity, until the star disappears, leaving only a ghost behind, a black hole.

This transformation does not await all stars. Smaller, less massive stars, like our sun, eventually become burnt out dwarves, when their fusion stops, slowly fading cinders.

But it’s possible that almost all the massive stars that dominated the early universe formed black holes when they died, because a black holes is simply what happens when enough matter is crushed into a small enough volume, dramatically warping the space around it.

DAVID ROSARIO: A river is a great analogy for the area right around a black hole. Here, I am far upstream, and the water is fairly placid. It’s not moving too fast. If I were to get into the water here and swim across, I’d be able to do that very easily. In the same way, if you’re far away from a black hole, you’d be able to get around with just a normal spacecraft, without too much trouble, and simple propulsion.

NARRATOR: But, the closer you get to the black hole, the stranger things become. The collapsed massive star crushes down so small and so dense, it ceases to have a physical surface at all, becoming an infinitely small point in space, exerting a profound effect on the space-time around it.

DAVID ROSARIO (Newcastle University): As the water gets closer to the waterfall, the speed of the water increases. If I were to jump into the water right here, the speed of the current would be so intense that I wouldn’t be able to swim against it, and I would be gradually pulled closer to the edge of the waterfall, until I reach a point of no return. And that’s the same around a black hole.

NARRATOR: Just outside the black hole, the fabric of space, itself, actually stretches inward towards the center.

DAVID ROSARIO: Not even stars, planets, people, even light cannot escape the pull of a black hole. It’s like a waterfall in the fabric of the universe.

NARRATOR: The black holes gravitational reach is not infinite.

URMILA CHADAYAMMURI: People have this idea that black holes suck, in the sense that they suck everything into them, but that’s not true. Black holes can only eat things that are within a certain distance away from them. If you’re further away, then the black hole has no way of eating you.

NARRATOR: But once in its grasp, you are lost forever. And this is the key to their mystery. The black hole’s interior is hidden from view, cut off from the rest of the universe by a boundary in space, the “event horizon.” Beyond this point, there is no escape. As we approach the event horizon, we get our first glimpse of the true weirdness of black holes.

DAVID ROSARIO: Ever since Einstein, we’ve viewed the fabric of the universe, not as something static, but instead something that’s fluid, something that bends and warps around objects with mass.

We call this space-time, a combination of space and time. See, Einstein’s insight was to realize that these two things are intimately connected, that when an object has mass, it not just bends space, but changes the passage of time, itself. In particular, the effect of a mass is to slow time down.

NARRATOR: In the region around the black hole, the warped space-time elongates light waves, distorting color.

DOUGLAS FINKBEINER (Center for Astrophysics | Harvard & Smithsonian): The event horizon is the place at which time stops when seen from far away. Someone who’s outside the black hole will see you get redder and redder, and your time will slow down, and you’ll kind of pass through the horizon, disappear forever.

NARRATOR: Black holes are like waterfalls in the fabric of the universe, where space contorts and time, itself, grinds to a halt, ensnaring light, making them lockboxes for the universe’s ultimate secrets.

STEPHEN HAWKING (Theoretical Physicist/Audio Clip): It is said that fact is sometimes stranger than fiction, and nowhere is that more true than in the case of black holes. Black holes are stranger than anything dreamed up by science fiction writers, but they are firmly matters of science fact.

NARRATOR: The vast majority of black holes are small, less than 20 miles across, and they usually wander alone through space. But if we turn our gaze towards the center of the Milky Way and journey inwards, through the gas and dust that shroud the galactic core, signs of something altogether different appear.

GRANT TREMBLAY: If you simply observe the stars in the very heart of our galaxy over about 20 years, you will observe them orbiting nothing. At the center of this swarm of stars is darkness. It’s a void.

NARRATOR: Scientists name this invisible enigma “Sagittarius A*,”although it is not a star at all.

ANDREW PONTZEN: Can you imagine how massive that object has to be to be able to pull entire stars into orbit?

NARRATOR: They believe it to be a black hole, more than 4,000,000 times the mass of our sun, many thousands of times more massive than any other in the Milky Way.

SUGATA KAVIRAJ: How did this monster come to live at the heart of the Milky Way?

NARRATOR: Sagittarius A* star is a supermassive giant, around which the entire galaxy spins, raising intriguing new questions about the role of black holes in our galaxy and the universe: How did it get there? How did it get so big? And what can it tell us about how black holes shape the cosmos?

BECKY SMETHURST: Would we even be here today without Sagittarius A*?

CHANDRA MISSION CONTROL: Just a few minutes away from the 26th flight of the shuttle Columbia with a crew of five.

KIM ARCAND: I think a night launch is particularly exciting.

CHANDRA MISSION CONTROL: We’re go for engine start. We have booster ignition and liftoff of Columbia.

CHANDRA MISSION CONTROL: Roger roll, Columbia, we’re looking in.

URMILA CHADAYAMMURI: Chandra is huge, about the size of a school bus. It’s the largest telescope to ever be launched by the space shuttle.

CHANDRA MISSION CONTROL: S.R.B. separation is confirmed.

KIM ARCAND: You’re stressed about the astronauts on board that are literally risking their lives to help us get a better view of the universe.

NARRATOR: In the summer of 1999, NASA’s flagship telescope for X-ray astronomy sets off from the Space Shuttle cargo bay.

GRANT TREMBLAY: Even two decades into its voyage of discovery, Chandra remains by far, the most powerful observatory that we have to observe the high energy universe.

NARRATOR: Almost 83,000 miles above the earth’s surface at its highest orbit, Chandra scans the sky with eight high-precision mirrors, engineered to detect X-rays emitted from extremely hot regions of the universe. For 14 years it searches among the exploding stars and clusters of galaxies, but then, on September 14th, 2013, Chandra chances on something else entirely.

IMOGEN WHITTAM: Chandra wasn’t looking for this at all, just happened to be looking nearby. So, it was a total surprise.

NARRATOR: As the telescope gazes into the constellation of Sagittarius, it aims to observe a large cloud of hot gas, but unexpectedly, it records a flash of X-rays just a few pixels across, coming from the seemingly empty space in the galactic core.

SUGATA KAVIRAJ: When we see something get very hot for a very short period of time, we get very excited. Something is causing it, something we can’t see.

NARRATOR: Some scientists believe the flash seen by Chandra is caused by an asteroid, ripped apart and burning up in a blaze hundreds of times brighter than the sun, releasing a burst of X-rays that Chandra can detect, almost 26,000 lightyears away.

JUDITH CROSTON (The Open University): If we see a level of X-rays being produced that’s so bright it can’t be explained by any other process, then we know that there must be a black hole there.

NARRATOR: It’s the behemoth at the center of our galaxy: “Sagittarius A*.

KIM ARCAND: You can take a telescope like Chandra and watch a black hole have a small snack, maybe like a human might have a little biscuit in the afternoon, and it’s something like an asteroid. And there will be a small sort of X-ray signature from that event.

SUGATA KAVIRAJ: So, it’s incredible that we can actually observe Sagittarius A*, which lies 26,000 lightyears away, actually eating something.

NARRATOR: But Chandra does not only look inwards, it also looks out, beyond the Milky Way. At the center of almost every large galaxy Chandra peers into, it finds evidence that our galaxy is hardly unusual.

REBECCA SMETHURST: We started to spot X-ray sources of light everywhere around the sky, and we started to realize something weird was going on in the centers of galaxies.

SHEP DOELEMAN: At the heart of most galaxies, we think now, there are supermassive black holes, black holes that weigh millions or billions of times what our sun does.

JUDITH CROSTON: It’s incredible that our modern X-ray telescopes, like Chandra, allow us to map out where these fascinating black holes are across the universe.

NARRATOR: Supermassive black holes seem to be an integral feature of the cosmos, but these supermassive objects raise questions: How do they form? And why are they so big?

BECKY SMETHURST: These things form over millions to billions of years. So, we can’t watch this happening. We can only see it at various different stages throughout the universe. And so we have to just piece it together, like a jigsaw puzzle.

NARRATOR: Some scientists theorize that the biggest and oldest black holes did not start life as stars at all.

PRIYA NATARAJAN: In the very early universe, we believe that you could have formed very massive black hole seeds by direct collapse of gas. So, these black holes are called “direct collapse” black holes.

NARRATOR: But the jury is still out.

KIRSTEN HALL: It’s possible that Sagittarius A* formed by direct collapse of material. What I think is more likely is that it formed by the death of a star.

NARRATOR: However Sagittarius A* was born, one thing is certain: it had to grow.

The newly formed Sagittarius A* begins to feast, gorging itself on, not just asteroids, but bigger game, like stars and massive clouds of gas.

IMOGEN WHITTAM: As it snacks on these nearby objects that wander into its path, it gets bigger and bigger and bigger.

NARRATOR: The black hole gains more mass and more gravitational power.

CHIARA MINGARELLI: But black holes that are a few times the mass of the sun can never grow to be a supermassive black hole just by eating gas and stars.

NARRATOR: How did Sagittarius A* speed up its growth? On September 14th, 2015, an international team of astronomers finds a clue, the aftershock of a truly titanic interaction: two colliding black holes.

GRANT TREMBLAY: The merger of two black holes, as you might imagine, is spectacularly energetic. It is so energetic that it causes ripples in the fabric of space-time itself, that propagate outward at the speed of light. And we have detected these ripples here on Earth with something we call “LIGO.”

KIRSTEN HALL: LIGO is an instrument that works by sending laser beams that bounce off of mirrors. When a gravitational wave passes by the earth, this changes the timing of the interaction of those laser beams.

DELILAH GATES: The stretching caused by a merger here on Earth is absolutely minuscule, but with advanced technology LIGO was able to do it.

NARRATOR: Many scientists now think that mergers like this are the key to how supermassive black holes like our own, grow so big. When another black hole wanders towards Sagittarius A*, they become locked in a gravitational embrace.

PRIYA NATARAJAN: First, it is sort of an intriguing dance. They kind of dance around each other, lose energy, and slowly spiral into each other.

CHIARA MINGARELLI: This dance gets faster and faster and faster and faster, until they finally merge.

NARRATOR: Sagittarius A* cannibalizes its cousin, creating ripples in the fabric of the universe itself.

IMOGEN WHITTAM: These mergers were fundamental to making Sagittarius A*, the monster that we see today. They happened billions of years ago, right at the beginning of Sagittarius A*’s life.

NARRATOR: More meals follow, stars, gas clouds, whatever strays too close. And as our black hole’s mass and influence grows, its surroundings are changing, too.

The sea of stars and gas around the black hole continues to grow, gradually evolving into the familiar spiral disk we call home: the majestic Milky Way, with the supermassive Sagittarius A* at its core.

SUGATA KAVIRAJ: So, when Sagittarius A* becomes a supermassive black hole, it really comes of age, and it acquires the ability to have a transformational impact on the evolution of the entire galaxy.

SHEP DOELEMAN: Black holes are the ultimate engines in the universe. When you think about a car, the first thing you’re interested in is, “How does it work?” You open the hood and you look at the engine of the car. With a black hole you’re asking, “I want to lift the hood up on an entire galaxy. How does a galaxy power itself, at its very heart?”

NARRATOR: The center of the young galaxy is rich with swirling gas and dust, more offerings to feast on.

This is a gluttonous period, a new era for Sagittarius A*, when the invisible giant has the power to sculpt the galaxy.

IMOGEN WHITTAM: As Sagittarius A* is gorging on food, the food that it’s waiting to eat is swirling around the central supermassive black hole, in this violent, energetic disk. And the matter is ripped apart by the gravity, which causes the protons and electrons to then make these twisted magnetic field lines.

HAKEEM OLUSEYI: Everything is rotating and orbiting, so at the center of this black hole, this accretion disk, you have a twisted magnetic field, almost like a tornado.

KIM ARCAND: Right before the material approaches that event horizon, that eternal prison, if you will, it can be redirected instead.

NARRATOR: And from the blazing tumult, the super-heated material is thrown out along the magnetic poles, two high-powered jets, launched out into the cosmos.

SHEP DOELEMAN: They can reach hundreds of thousands of lightyears from the black hole itself.

NARRATOR: It’s only recently that we’ve begun to grasp the huge influence of Sagittarius A* on our galaxy and the role that those super-powered jets may have played.

Just over a decade ago, astronomers made a completely unexpected discovery.

BECKY SMETHURST: It was this whole piece of our galaxy that we never knew was there before. It would be like finding a brand new continent on Earth.

NARRATOR: The Fermi Space Telescope was built to detect gamma-rays, the most energetic radiation in the universe.

DOUG FINKBEINER: Fermi is roughly a hundred times as sensitive as previous gamma-ray telescopes, so it has the sensitivity to see things that we just simply couldn’t see before.

NARRATOR: Orbiting the earth once every 96 minutes, Fermi constructs a map of the cosmos and uncovers an invisible landscape, the most energetic regions of the galaxy, highlighted across the sky.

KIM ARCAND: So, we pointed the Fermi telescope towards our very own supermassive black hole, and we had a picture of what that area sort of looked like, in our minds, at least. But then Fermi revealed something completely astonishing and unexpected.

NARRATOR: Emerging from the plane of the Milky Way are two enormous bubbles, each one stretching 25,000 lightyears, together reaching half the width of the galaxy.

DOUG FINKBEINER: If you could see in gamma-rays, the Fermi bubbles would be about the biggest thing you see on the sky.

DAVID KAISER (Massachusetts Institute of Technology): They look like huge dumbbells going straight up and straight back from the center of the black hole.

NARRATOR: The bubbles match the imprint scientists expect an enormous eruption from Sagittarius A* to leave on the galaxy.

JUDITH CROSTON: We had had some clues that the Milky Way might have had a more energetic and active past, but the incredible thing about the Fermi bubbles was that they suddenly gave us concrete evidence that the Milky Way was much more energetic, at some time in its history.

NARRATOR: When our black hole gorges, it unleashes a towering inferno of superheated matter.

GRANT TREMBLAY: A supermassive black hole can impart something like a trillion- trillion-atomic-bombs-per-second’s worth of energy.

SHEP DOELEMAN: If we were to be in the line of fire of one of those jets, it would be catastrophic for us. We’d be vaporized.

NARRATOR: Every planet in the jet’s path could have its atmosphere stripped away.

But further out in the galaxy, these violent outbursts from Sagittarius A* may have played a surprising role, because the hot gas displaced by a supermassive black hole has a calming effect on the galaxy that hosts it.

KIRSTEN HALL: In order for stars to form, you need very cold and very dense gas, because stars form through the collapse of material.

URMILA CHADAYAMMURI: So, instead, if you have something like a supermassive black hole that is sending out these hot jets into the galaxy around it, those jets are going to heat up the gas. Now, the gas is no longer cold enough to collapse and then form a star.

SHEP DOELEMAN: There’s a symbiotic relationship between the supermassive black hole at the center and its host galaxy. And this relationship determines the rate at which stars form, planets form, and ultimately, in some sense, why we are here.

NARRATOR: After spending billions of years consuming the gas, dust and stars around it, there is little left to feast on. Our black hole falls dormant.

Today, the Milky Way has entered an era of calm, and Sagittarius A* is a sleeping giant, the enormous bubbles spotted by the Fermi telescope, echoes of a lively past.

DOUG FINKBEINER: You never want to assume that you live at a special time in the history of the universe, but it is kind of a special time, in that, right now, the black hole is very quiet, and it must have been much more active a few million years ago.

NARRATOR: As our understanding has grown, our picture of black holes has transformed: no longer sinister monsters, but agents of change and creation, sculptors of the cosmos.

DAVID ROSARIO: We are far from unlocking all the secrets of our galaxy’s supermassive black hole. And, in fact, the stuff that remains is probably the most interesting: what happens inside a supermassive black hole and at its event horizon.

STEPHEN HAWKING (Audio Clip): Black holes challenge the most basic principle about the predictability of the universe and the certainty of history. Nothing could get out of a black hole, or so it was thought.

NARRATOR: Black holes are where two of our greatest theories collide and clash.

SHEP DOELEMAN: So, you’ve got these two primal forces in the universe: gravity, which we all understand and feel with our bones, and then you’ve got quantum mechanics, which governs the theory of the ultrasmall, how atoms and nuclei come together. The black hole is where gravity and quantum mechanics finally meet.

JIM GATES: When we try to take the mathematics of the very large and try to combine that with the mathematics of the very small, instead of matching, they get into a fight. And so, we don’t have a consistent way to describe both.

NARRATOR: We can begin to probe this deep mystery by investigating the heart of Sagittarius A*. Scientists have studied dozens of stars in its orbit, some passing just a few billion miles from the event horizon, a hair’s width on galactic scales. And these flybys could have catastrophic consequences, because some of these stars likely have planets in orbit, planets that may stray too close: moths to a flame, pulled from their parent stars towards the abyss.

GRANT TREMBLAY: So, imagine you’re some alien civilization, looking up at your lovely home star, S2, in the sky. And one day, the thing starts wandering closer and closer to what we call the “tidal disruption radius” of Sagittarius A*, this four-million-solar-mass black hole.

IMOGEN WHITTAM: If you fell into a black hole, you’d pass the event horizon and actually, bizarrely, you’d see nothing. There’s no physical barrier. There’s no big line in space saying, “point of no return.” You would just drift, very casually, gently across the event horizon.

NARRATOR: If we could stand on such a planet and look outwards, we’d see something spectacular.

HAKEEM OLUSEYI: You’d see a distorted universe. And, in fact, you see it distorted in both time and space.

IMOGEN WHITTAM: You’d see it playing out at an amazingly fast speed. The rest of time would play out unbelievably fast in front of your eyes.

NARRATOR: But eventually, tidal and gravitational forces become too strong, stretching space and everything in it.

IMOGEN WHITTAM: Your feet would be pulled more strongly by gravity than your head, so you’d be stretched out into a giant string. And eventually, you’d be one long string, one atom thick. We call this “spaghettification.”

NARRATOR: Boulders become rocks, rocks become sand, whose very atoms are then pulled apart. Gravity and the quantum world collide. Ahead: the heart of the black hole, the singularity, where all journeys in terminate.

HAKEEM OLUSEYI: Our idea of a singularity is that everything is compressed beyond what it can be, until it’s nothing but yet still exists. That is…wow.

NARRATOR: Over trillions of years, all the stars around Sagittarius A* will gradually fade out of existence…

SUGATA KAVIRAJ: Long after the last ever sun sets on any planet, black holes will continue to roam the universe.

NARRATOR: …the final dark age.

GRANT TREMBLAY: If nothing can ever escape, if this is some eternal prison, is that the end of the story?

NARRATOR: Perhaps not, because scientists now believe that even Sagittarius A* will die. And its death will come at the hands of what might seem an inconsequential effect, first described almost five decades ago.

CHRIS DONE (Durham University): So, in 1975, Stephen Hawking published this amazing paper, showing that black holes aren’t absolutely, completely black. They glow very, very faintly. They have a temperature associated with them. And you can write that temperature very simply in an equation that’s just beautiful.

It links together so many different parts of physics. It’s got gravity in it. It’s got the mass of the black hole in it. It’s got the speed of light. It’s got constants relating to atomic physics, the micro world. And it’s putting all of these together and giving us a temperature.

NARRATOR: Hawking’s equation has huge implications for the future of the black hole.

CHRIS DONE: So, if something has a temperature, it’s glowing, it’s radiating. Like, when you put your hand close to a fire, you can feel it. And that losing energy, for a black hole like Sagittarius A*, over timescales that are hugely long, it’s going to evaporate away. It’s going to disappear.

NARRATOR: Very gradually, this Hawking radiation will erode away Sagittarius A*, until, many trillions and trillions of years into the future, in a final burst of light, our black hole will disappear. And then the Milky Way will be completely dark, for all eternity.

CHRIS DONE: So, why does it matter if these black holes disintegrate in the far distant future? Well, the discovery of “Hawking radiation” raised some profound questions in physics.

If I was to set fire to this piece of paper with Stephen Hawking’s equation written on it, what happens to all that information as it burns away, as it radiates away? Do we lose it from the universe forever?

Maybe, if I could sweep up all the ash, if I could find all the photons and reconstruct them, maybe I could reconstruct that piece of paper, even the equation written on it.

So, does this also apply to black holes? What happened to all the information contained on all the material that ever fell into a black hole? And as a black hole evaporates, what happens to it?

STEPHEN HAWKING (Audio Clip): Black holes ain’t as black as they are painted. They are not the eternal prisons they were once thought. So, if you feel you are in a black hole, don’t give up. There’s a way out.

NARRATOR: If information somehow escapes from Sagittarius A*, as it evaporates away, the implication is profound.

Scientists now believe that every star, asteroid, planet, everything that ever fell into Sagittarius A*, may live on; every aspect and position of every particle, encoded as information, all that you would, theoretically, need to put the whole back together.

REBECCA SMETHURST: So, the memory of every single thing that’s fallen into, become part of, Sagittarius A* in the Milky Way, hasn’t been lost. It’s still there. It’s just that we can’t access that now. But maybe we might be able to read the ashes of that memory in the far future of the universe.

NARRATOR: But how can anything escape a black hole’s grip?

ANDREW PONTZEN: The defining fact of a black hole is that nothing should be able to get out. And yet, when you look at Hawking radiation, it seems to be suggesting that quantum physics does connect up the inside back to the outside. We just don’t really know how.

NARRATOR: Black holes force us to consider nature in entirely new and mind-bending ways.

DELILAH GATES: People aren’t at all certain about the resolution to what happens when we throw things into black holes. As far as where the information goes, it’s still an open question.

DAVID KAISER: Maybe it gets sent to a portal to another dimension, maybe it gets pumped into some other branch of a larger multiverse.

NIAL TANVIR: Some people imagine that black holes are really just a kind of quantum fuzz, a fuzzball.

SHEP DOELMAN: Some people think that all the information that fell into the black hole is somehow encoded on its surface in a hologram.

RICHARD ANANTUA (Center for Astrophysics | Harvard & Smithsonian): But we’re not really privy to any of this information. And if we want to find out, we’d have to go in.

NARRATOR: Whatever the solution proves to be, it will have ramifications far beyond the black hole itself.

CHIARA MINGARELLI: This theory of quantum gravity that’s so elusive right now, that is what we would need to describe what’s happening inside black holes, could either be the most exciting development to happen in the next decade or maybe even the next century, or it could be an alarm bell, going off in our heads, that maybe Einstein’s theory of gravity is not the final word on gravity.

NARRATOR: Solving the mystery of black holes may be our best chance to complete the picture of nature that has eluded us for the last century.

SUGATA KAVIRAJ: So, perhaps the important thing isn’t what the answer turns out to be. The important thing is that we will gain a fuller understanding of the cosmos by studying these remarkable objects.

HAKEEM OLUSEYI: Studying the universe has completely changed our universe. We have to rethink everything over and over again, like, it’s almost like, “tear up the universe we know and write a new one.”

NARRATOR: We’re still a long way from fully comprehending the secrets of black holes, but we’re beginning to lift the veil. Far from being a mere cosmic aberration, black holes fundamentally shape our universe.

SUGATA KAVIRAJ: So, it’s extraordinary to think that we might be fundamentally connected to something that we didn’t know existed for the vast span of human history.

HAKEEM OLUSEYI: The beautiful thing about black holes is that they’re such a rich source of information. We’ve learned so much about the universe from studying black holes: space, time, the very fundamental nature of reality.

NARRATOR: Bit by bit revealing the deepest mysteries of the cosmos.

ANDREW PONTZEN: We’re in a golden age of discovery about black holes. We understand how they merge; we’ve discovered their colossal jets, and we’re beginning to see them, not just as destroyers, but also as creators and sculptors. And all that is just the beginning.

REBECCA SMETHURST: Our story’s happening now, but black holes, they are going to outlive us by trillions of years. Their story is just getting started.

NOVA Universe Revealed: Milky Way

by allynh » Thu Nov 04, 2021 2:16 am

Here we go again with another "Just So" story.

The only things of "fact" that the episode has is the Hubble telescope, and the Gaia satellite, everything else is made up.

BTW, is it just me, or do these people look like children. Why are there no old astronomers anymore.

NOVA Universe Revealed: Milky Way
https://www.pbs.org/wgbh/nova/video/nov ... milky-way/
PREMIERED NOVEMBER 3, 2021 AT 7PM ON PBS
Straddling the night sky, the Milky Way reminds us of our place in the galaxy we call home. But what shaped this giant spiral of stars and what will be its destiny? NOVA travels back in time to unlock the turbulent story of our cosmic neighborhood, from its birth in a whirling disk of clouds and dust to colossal collisions with other galaxies. Finally, peer into the future to watch the Milky Way’s ultimate fate as it collides with the Andromeda galaxy, over 4 billion years from now.

TRANSCRIPT
Universe Revealed: Milky Way

PBS Airdate: November 3, 2021

NARRATOR: The Milky Way, our home, formed not long after the Big Bang, one of trillions in the universe. This is our galaxy, billions of planets orbiting billions of stars. We are only just beginning to understand its true place in the universe.

GERRY GILMORE (University of Cambridge): It was only a hundred years ago, people thought our Milky Way was the entire universe.

PAYEL DAS (University of Surrey): If we really want to understand where we come from and how the galaxy was formed, we can’t just look in our cosmic, sort of, backyard. We need to look much further afield.

NARRATOR: And when we do, we discover a universe in turmoil…

VASILY BELOKUROV (University of Cambridge): Our history is made up of multiple collisions and interactions with our neighbors.

RANA EZZEDDINE (University of Florida): Our Milky Way is not static. It is dynamic, and it had such a rich, dynamic history.

NARRATOR: …and our place in it, far from secure.

DAVID ROSARIO (Newcastle University): A collision can change the structure of a galaxy, reorders the stars, and so, you end up with something that looks different, that behaves differently.

NARRATOR: Now, we can see our galaxy’s future and its inevitable end.

JEN GUPTA (University of Portsmouth): The Andromeda galaxy is actually heading towards us at about 250,000 miles per hour.

GERRY GILMORE: It will be a really nice sight, actually. Just watch it coming, I mean, there’s nothing we can do about it except sit back and enjoy the view.

MICHELLE COLLINS (University of Surrey): It’s all coming together to tell us about how we got here and what our place in the universe really is.

NARRATOR: The Milky Way, right now, on NOVA.

Above us in the night sky, visible all around the world, the Milky Way wraps its arms across the sky, a band of stars like no other.

GRANT TREMBLAY (Center for Astrophysics | Harvard & Smithsonian): When the Milky Way is up overhead, the skies are so brilliantly bright that I swear the band of the Milky Way, the disk of our own galaxy, quite literally casts a shadow.

MICHELLE COLLINS: Our Milky Way is this really incredibly beautiful place. It’s this wonderful collection of beautiful stars, gas and dust that all kind of swirls together, almost like an abstract painting.

PAYEL DAS: We’ve been trying to understand the band of stars that stretches across the night sky since the time of the ancient Greeks.

NIA IMARA (Astrophysicist): Humans have been looking up at the night sky since the dawn of time, because we want to know what’s out there.

NARRATOR: Because the story of our galaxy is the story of every one of us.

GERRY GILMORE: How does it all fit together? What are we part of? Can we understand it?

NARRATOR: The Milky Way galaxy takes its name from the dense band of stars that we see from Earth, when, in fact, it’s a structure that entirely surrounds us. Every star in the sky, is part of it, including our sun.

SOWNAK BOSE (Center for Astrophysics | Harvard & Smithsonian): When looking into the night sky, you would see this band of stars stretched across it, which actually corresponds to the disk of the Milky Way. So, we actually live inside the Milky Way.

RANA EZZEDDINE: Our galaxy is a spiral galaxy. And we can build up this picture, which we have been doing for hundreds of years, so far, since the first astronomers, like Galileo, to, kind of, build up this beautiful picture of our Milky Way.

PAYEL DAS: Right in the center you have a bulge, then you have a pancake-like structure. That’s the disk, and that’s where we are. And then further out, you have a faint halo of stars that goes quite far beyond the disk.

MICHELLE COLLINS: It’s this beautiful spiral structure of hundreds of billions of stars, all orbiting around a supermassive black hole, right at the center of the galaxy.

NARRATOR: The Milky Way’s complex structure has taken billions of years to evolve, and yet, it’s one of the most familiar forms in nature.

GERRY GILMORE: So, let’s start at the very center. And, in the center, there is a very old bulge, that contains most of the old stars. And this is the remnants of the first stars that formed in our part of the universe. Right at the very heart of it, there is a supermassive black hole. That is the core of the Milky Way, as we know it. And then, around that’s the bulge, then there’s this big bar structure, mostly old stars. And that’s what drives the spiral arms.

So, we can then say, “Where are we in all of this?” We know pretty well where the sun is and, hey, presto, one sun. And it will be about there: roughly halfway from the center to the outer spiral arm structures. And this is where the sun lives today.

NARRATOR: The Milky Way’s elegant spirals are the signature of its dynamic history. The challenge is how to observe it and tease out that history, from our position on the inside.

MICHELLE COLLINS: One of the problems of trying to study the Milky Way from our position here on Earth is that it’s really hard to get a sense of what the galaxy looks like, overall.

PAYEL DAS: So, if we really want to understand where we come from and how the galaxy was formed, we can’t just look in our cosmic, sort of, backyard. We need to look much further afield.

NARRATOR: Clues to how the Milky Way formed and evolved emerged in the 1990s, with the launch of the most ambitious space telescope at the time.

HUBBLE SPACE TELESCOPE MISSION CONTROL: Five, four, three, two, one, and liftoff of space shuttle Discovery with the Hubble Space Telescope, a window on the universe.

Standing by for separation. Solid rocket boosters have separated.

PAYEL DAS: The Hubble Space Telescope is one of the greatest feats in space missions of human history.

GRANT TREMBLAY: This 2.4 meter piece of glass, we turned it on our universe and it has enabled untold advances.

NIA IMARA: Images from Hubble transformed astronomy, transformed science.

NARRATOR: Hubble isn’t just focused on the Milky Way. It also looks beyond, much deeper into space.

DAVID ROSARIO: The data from Hubble is unsurpassed. It gives us the sharpest views of galaxies and the distant universe.

PAYEL DAS: Hubble’s a little bit like a time machine. It’s able to pick up light from galaxies that come from very far away. And because they’ve come from very far away, we’re looking at them in completely different time, far back in time.

NARRATOR: To look far back in time, Hubble trains its gaze on one tiny blank patch of sky, for over 11 days.

PAYEL DAS: What appeared was pretty incredible.

RANA EZZEDDINE: We were able to see galaxies in this ultra-deep field that is farther away than we’ve ever, ever looked.

PAYEL DAS: So, it’s really given us an idea of how many galaxies are out there and the variety of galaxies out there.

GRANT TREMBLAY: It’s a very hard number to estimate, but it is absolutely in the trillions. Their morphology can be incredibly complex, big train wreck mergers or absolutely stunningly beautifully round, grand design spirals and everything in between.

NIA IMARA: There are starburst galaxies that are generating new stars at prodigious rates. And there are small galaxies, which are my favorite. We call them dwarf galaxies. And they may be thousands of times less massive than the Milky Way, but they’re actually the most common galaxy in the universe.

NARRATOR: Hubble tells us there are trillions of galaxies in the universe. And by focusing on the ones that are farthest away, it looks deep back in time, giving us a picture of what galaxies look like in their infancy.

And they started forming in an era of immense cosmic activity, not long after the universe began. Before the Milky Way forms, space is filled with a vast structure known as the “cosmic web.” Hydrogen and helium gas collect along the web’s vast filaments, but the web itself is made from something more mysterious. It’s called “dark matter.”

DAVID ROSARIO: Dark matter is something that has gravity but produces no light. It surrounds us, in fact, it dominates the mass in our own galaxy, and yet we don’t know what it is. We can’t touch it, we can’t feel it.

MICHELLE COLLINS: Galaxies really need dark matter, because it’s, kind of, like, the glue that binds them all together. You can almost say it’s like the seed of galaxy formation. It creates these huge structures into which ordinary matter falls, and then that matter all gets compressed and can turn into stars. And that really is, then, what seeds galaxy formation, as a whole.

NARRATOR: The first stars are born where the filaments cross and dark matter is at its densest, drawing large amounts of gas together, until it collapses under its own gravity, causing stars to ignite. New stars, in their billions, are bound together by gravity, orbiting a common center.

These are the first galaxies, among them, the Milky Way, in its embryonic form, a whirling disk of gas and stars surrounded by an invisible halo of dark matter.

Across the universe, hundreds of billions of galaxies are forming. Some, a few dozen, are born very close to our own Milky Way. Over time, gravity draws these galaxies ever closer, to form what we know as the Local Group.

RANA EZZEDDINE: Our Local Group is a set of galaxies that lies in a volume of the universe that we believe is gravitationally bound together, meaning that these galaxies are close enough that at some point they might all combine together or collide together to form one big, large galaxy.

MICHELLE COLLINS: The galaxies within the Local Group can all feel one another’s gravity, so they’re all, sort of, slowly moving together, with time.

NARRATOR: Just three-billion years after the Milky Way began, it rises in the night sky of its first planets, but with only half the stars and a more irregular structure than the mature galaxy we see today.

So, how did our galaxy get its spirals? To answer the question, a new spacecraft is built. “Gaia” will look directly at the Milky Way itself.

Its designers are determined to overcome an age-old problem: how to measure the true distance between stars.

GRANT TREMBLAY: Being able to determine the distance to objects is one of the most fundamental things you need to do to understand the structure of our universe.

NARRATOR: To measure the distances accurately, Gaia’s engineers must devise an orbit for the craft, big enough that it can measure the same star from two points, very far apart, called a “parallax” measurement. Gaia will need to travel almost a million miles from Earth.

GAIA LAUNCH ANNOUNCER: Attention pour la décompte finale. Dix, neuf, huit, sept, six, cinq, quatre, trois, deux, un. Top. Décollage!

GERRY GILMORE: I’ve been involved in Gaia since the very beginning of it. It was a beautiful launch, really spectacular.

NARRATOR: The spacecraft shares the name of the ancient Greek Earth goddess, Gaia.

GERRY GILMORE: It took four minutes. You could see the flame of the rocket, and you could see the individual stages popping off. Then, they got into this critical state, where they had to open up the sun shields.

It was critical that this opened up and protect the payload from the sun. And that was the “do-or-die” moment.

NARRATOR: Gaia’s mission is to map the true positions of a billion stars in our Milky Way, nearly all of them for the first time.

VASILY BELOKUROV: Before Gaia, we just looked at the images of our galaxy, we were missing half of the information.

GERRY GILMORE: Gaia is the first ever precision distance measuring machine that mankind has ever had.

NARRATOR: So, how is it possible for Gaia to map the Milky Way so accurately from within?

First, it travels to its distant vantage point called L2; a gravitational sweet spot. It can hold here, with minimal fuel use, as it follows the earth in its extensive orbit around the sun.

DAVID ROSARIO: Astronomy has always been at the forefront of technology, but the kind of technology we work with right now is absolutely amazing.

NARRATOR: With just a whisper of nitrogen, to help Gaia’s telescopes sweep smoothly through 360 degrees, four times a day, it makes over one-and-a-half-million observations an hour.

After four months, it has looked at the whole sky at least once.

Gaia gathers data on the brightest stars across the whole sky, stars within the disk of the galaxy, from the center to the halo and beyond. After it has travelled millions of miles in its orbit, it observes the same stars from a different vantage point. After nearly two years of almost non-stop sky-scanning, scientists can triangulate the true position of over a billion stars, for the most accurate map of the galaxy ever created, the Gaia map.

VASILY BELOKUROV: The Gaia data has allowed us to see our own galaxy like never before.

RANA EZZEDDINE: I think that Gaia opened up a really new axis of information to us that we just have never imagined it would do.

GRANT TREMBLAY: These are like having completely, you know, revolutionary cartographers make an entirely new map of our home galaxy.

NARRATOR: Finally, astronomers have their Holy Grail: the Milky Way, mapped in three dimensions.

GERRY GILMORE: This is the first ever honest 3D picture of the Milky Way. It’s not a simulation from a computer and it is not an attempt at guessing the structure from approximate data. Every one of those stars is individually measured to high precision.

So, this means that we can move ourselves around, through this, and see, well, what does this bit of the Milky Way actually look like? And you decide you want to look at it from far away and you can do that, or you can zoom in close and say, “I want to know how that star cluster works. I’ll go and sit inside it.”

Gaia can tell the difference between a star that’s at the front of that cluster and the star that’s at the back of that cluster, even though the cluster itself is 5,000 lightyears away. Gaia is not only measuring where things are, to delightful precision, but, equally, you can see things moving. And it’s actually the moving that’s the critical bit.

NARRATOR: In addition to mapping stars in three-dimensional space, Gaia captured another dimension, the result of its repeated trips around the sun: time.

This data could help us understand how our galaxy evolved.

DAVID ROSARIO: Gaia doesn’t just tell us where the stars are in the sky, but also how fast they’re moving across the sky and towards us. And that’s an essential bit of information to understand how things change over time.

NARRATOR: Once scientists know how a star is moving, they can use Newtonian mechanics to calculate where it is going. And, using the same calculations, they can reverse the motion of the star to uncover where it has been.

This new data is revolutionizing a field of science known as “galactic archaeology.”

DAVID ROSARIO: Galactic archaeology is the process of identifying the history and the motion of stars, so you can figure out where stars come from, how old they are and how their motions change over time.

PAYEL DAS: What’s been really incredible about Gaia is, if we couple it with spectra that we’re observing back on Earth, we’re able to date the stars and really use them as the fossils that they’re supposed to be. So, this means we can work out what the fossils tell us about the evolutionary events that happened in the Milky Way’s past and then date them, so put them in chronological order.

RANA EZZEDDINE: So, we combine everything together in order to get a really clear understanding of how the Milky Way came to be.

NARRATOR: This new data from Gaia has helped scientists spot a pattern between the Milky Way and our neighborhood cluster of galaxies, the Local Group.

PAYEL DAS: The important thing to know about our galactic neighbors and the Local Group is that nothing’s actually sitting still. Gravity means that we’re all moving towards or away from each other and we’re sort of playing a dance out there.

NIA IMARA: Gravity is the great cosmic attractor.

VASILY BELOKUROV: This dance of the galaxy and its neighbors have been going on for billions of years.

NARRATOR: Gaia is only just now revealing the steps to this intricate intergalactic dance.

SOWNAK BOSE: When the Gaia satellite started producing its data and astronomers started analyzing this data, there was something rather curious.

MICHELLE COLLINS: A large sample of stars were found that seem to be rotating in the opposite direction to the majority of stars in the Milky Way disk. And that’s really unusual. And it was really surprising.

GRANT TREMBLAY: So, that means that not all of the stars that make up our galaxy, the Milky Way, were actually born here.

MICHELLE COLLINS: They probably came from a different galaxy altogether. So, they’re almost these alien stars that have been brought in.

NARRATOR: Gaia’s data led scientists to make an astonishing discovery.

DAVID ROSARIO: So, the most mind-blowing thing is that those stars are the remnants of a humongous collision, and they actually come from another galaxy.

NARRATOR: If we could travel back in time 10-billion years and land on one of the earliest planets within our Milky Way, we’d see something spectacular in the night sky: billions of stars coming into view, heading towards us. The Milky Way is about to collide with another galaxy from our Local Group, called “Gaia-Enceladus.” A quarter of the size of our galaxy, Gaia-Enceladus is drawn into the Milky Way, bringing disorder to its flat disk.

GRANT TREMBLAY: When you look at a galaxy merger, it looks like an incredibly violent process. But it’s actually something that’s incredibly elegant, and that is because galaxies are ultimately mostly empty space. And so, when galaxies collide or crash together, they pass through one another like ghosts. The chance for a star-star collision in a galaxy merger is actually exquisitely low.

SOWNAK BOSE: It’s really quite a beautiful process, because the way in which the mutual gravity of these two galaxies actually interact with one another causes one to start, sort of, spiraling around. Once it plunges in, it spirals around it and then comes back and returns. So, it’s kind of like, you know, two objects in a, sort of, celestial ballet, around one another.

DAVID ROSARIO: A collision can change the structure of a galaxy, reorders the stars, and the galaxy gives them new orbits, move the gas into different places in the galaxy. And so you end up with something that looks different, that behaves differently.

NARRATOR: The invisible driver of all these interactions is the same stuff that formed the galaxies in the first place: dark matter.

DAVID ROSARIO: Because it accounts for most of the gravity in the galaxy, it is dark matter that determines how violent the collision is, how rapidly and with what intensity galaxies come together when they collide. In many ways, it determines how galaxies end up after a collision.

NARRATOR: Just a few billion years after the Milky Way formed, already much more massive than Gaia-Enceladus, the Milky Way’s gravity overwhelms its neighbor, absorbing it entirely. The Milky Way is bigger by a billion stars.

DAVID ROSARIO: For the first time ever, we have seen how our Milky Way has grown bigger.

MICHELLE COLLINS: What we’ve learnt from this collision is really about how much richer our galaxy grew, but it doesn’t actually tell us about us yet.

NARRATOR: To find out how our solar system got here, scientists have been tracing the history of another unusual group of stars. They loop around our galactic disk in a spectacular trail called the “Sagittarius stream.”

MICHELLE COLLINS: So, the Sagittarius stream is really interesting, because it might actually help us understand where we came from.

SOWNAK BOSE: It is what’s known as a tidal stream, which is a stream of stars that have been stretched across the night sky due to the gravity of the Milky Way.

RANA EZZEDDINE: The Sagittarius stream is so big that it goes all the way up and even all the way down, so we can just carry the Milky Way from its handle. It’s really, really large stream.

NARRATOR: The trail of stars we see today is named after the galaxy that they used to belong to, “Sagittarius dwarf.”

GERRY GILMORE: The Sagittarius galaxy was discovered by a student and myself in the 90s. Most of the Sagittarius galaxy is actually spread out in two streams, one in front and out the back, like giant comet tails wrapping around the entire sky, going out for maybe 100,000 lightyears away. We could see these, but it wasn’t possible to understand how they got there.

Now, with Gaia, we have the motions of these stars, so we can see what direction they’re moving in, which ones are going fast, which ones are going slow. For the first time ever, it’s been possible to say, “Ah, this is what happened.”

SOWNAK BOSE: The Sagittarius stream is essentially the tidal debris that has been left over when a dwarf galaxy, the Sagittarius dwarf actually, plunged into the Milky Way.

NARRATOR: By studying the stream of stars, scientists have uncovered the story of a much more recent galactic collision, this time with a much smaller galaxy.

GERRY GILMORE: When the Sagittarius galaxy orbited into the Milky Way, it came, foolishly, rather far in.

NARRATOR: As it dives toward the Milky Way, the dwarf galaxy begins to have its stars pulled off.

GERRY GILMORE: When it goes through the disk, it punches a hole in the disk, and the stars get put in this particular patterns, and it’s got stretched into these two great long streams.

NARRATOR: The much smaller galaxy encroaches upon the Milky Way, just like Gaia-Enceladus did. But the timing is intriguing, because this collision happens just before the birth of our own solar system.

GRANT TREMBLAY: One of the most important consequences of galaxy mergers, like the destruction of the Sagittarius dwarf galaxy by the Milky Way, is a new, fresh injection of gas into the galaxy, right? And it is gas, particularly cold gas, that is the fuel from which all stars are born.

PAYEL DAS: For star formation to occur, basically, the colder the better.

NARRATOR: The most important gas that the collisions bring is made of one of the oldest and most ubiquitous elements in the universe.

DAVID ROSARIO: So, what I’m listening to here is the lifeblood of our galaxy, hydrogen. We can detect it with our radio telescopes, like in this case, pointing right at the Milky Way. Hydrogen is the most common element in the universe, and it’s in our own galaxy.

We don’t see gas with our eyes, and therefore we are not used to the idea of there being plenty of gas in the Milky Way. But if you use a radio telescope, you can see it. You can look at the radiation coming from that gas, and that’s exactly what we’re doing right now.

This gas is connected to stars deeply. It’s what stars form from. If this gas wasn’t there, stars would never have formed.

NARRATOR: Hydrogen was created shortly after the birth of the universe, and it has always been spread throughout the Milky Way, but not evenly. It clumps together in dense clouds that, in this iconic image, extend up to 30-trillion miles. Scientists call them stellar nurseries, where temperatures are low enough for gas to condense.

NIA IMARA: Stellar nurseries are some of the largest, coldest and certainly among the darkest regions within any galaxy. If you were to fly through a stellar nursery, it would be extremely cold and extremely turbulent and chaotic place, pervaded by magnetic fields and charged particles streaming throughout.

It might be glowing a little bit, and as you approach closer and closer, you would realize that it’s actually heating up a bit. It’s actually becoming warmer. You would perhaps surmise that this is where a new group of stars is being born.

MICHELLE COLLINS: Hydrogen can be thought of as the lifeblood of galaxies, because it’s the first building block of stars. In the center of a star, it’s fusing hydrogen together all the time to produce helium, and that gives off energy, which allows the stars to, sort of, light up.

NARRATOR: When the Sagittarius dwarf galaxy collides with our Milky Way, it brings more hydrogen to these clouds, triggering a new era of star birth.

SOWNAK BOSE: When galaxies interact with one another and they collide with one another, what typically happens is that you actually get a big burst of stars formation occurring, and that’s primarily because you are essentially bringing in a new source of star-forming fuel into the Milky Way.

NARRATOR: This era coincides with the birth of our own sun, 4.6-billion years ago.

PAYEL DAS: The jury’s still out, but we think that the start of the sun could have formed in that first enhancement in star formation.

RANA EZZEDDINE: The timing of the collision between the Milky Way galaxy and the Sagittarius dwarf galaxy coincides with a peak in star formation that we see happen in our Milky Way. And we know that the age of the gas in which our solar system was formed lies very close to this spike in star formation.

GRANT TREMBLAY: It is certainly possible, right, that our own solar system is anchored around a star that was born from gas that did not originate in our home galaxy. It was taken. It was pulled or consumed by the Milky Way, when it ripped apart a satellite galaxy, maybe even the Sagittarius dwarf.

NARRATOR: For a small galaxy, Sagittarius dwarf has had a big impact, and not just by triggering star birth. It plunges back and forth through the Milky Way as the galaxies become enmeshed, which likely contributed to the formation of the spiral arms. But its influence is fast fading.

SOWNAK BOSE: The question as to whether the Sagittarius dwarf galaxy is still around kind of depends on what you, what you, kind of, end up thinking of as being a galaxy after a certain point. It is really a galaxy that is in the process of being totally disrupted. And one day it will end up merging with the center of our galaxy. So, in in some sense, it’s only the sort of memory of the galaxy that is left behind.

NARRATOR: When we look up at the night sky, it’s easy to think of the Milky Way as static, but we now know it’s evolved through a turbulent history of collisions and mergers.

RANA EZZEDDINE: I think that Gaia opened up this whole new vision for us of…that our Milky Way is not static. It is dynamic and it had such a rich, dynamic history.

NARRATOR: But none of it is random. The force that causes galaxies to form, merge and evolve is gravity.

GRANT TREMBLAY: The thing that ultimately sculpts how those galaxies look is gravity. It’s not the collisions. It’s gravity: it’s the stars within those galaxies tugging on one another; and it’s the underlying dark matter, halos of those galaxies, merging together.

MICHELLE COLLINS: So, we’re actually at a really exciting time now in astronomy, because we can tell the story, not only of how our galaxy came to be and how everything led up to now, but we can also start to peer into the future and see what’s in store, what’s yet to come for the evolution of our galaxy.

NARRATOR: The more we learn about the Milky Way and its dynamic history, the more incredible it seems that we ourselves, orbiting just one star among billions, have been able to figure out our galaxy’s story, written in the stars. And we are now poised to map out its ultimate fate.

JEN GUPTA: The Milky Way is no stranger to galactic collisions. As we look around the night sky, we see evidence that our Milky Way galaxy has had these interactions with galaxies before. But what’s coming next is something on an entirely different scale.

This faint smudge of light that you see, right there, in the center of the image, it’s not some condensation on the lens or a cloud in the sky above us, this is an entire other galaxy, a huge galaxy, two-and-a-half-million lightyears away from us. To put that into units that humans can try to understand, this faint smudge of light is about 15-billion-billion miles away.

NARRATOR: This galaxy is called Andromeda and is set to play a defining role in our galaxy’s future.

The Hubble Space Telescope has taken extraordinary images of Andromeda. Compared to the disk of the Milky Way, Andromeda seems tiny, when in fact it’s anything but. It’s our largest neighbor in the Local Group, with the same spiral structure and the same long history of feeding on smaller galaxies.

JEN GUPTA: This image, right here, is actually ridiculous, when you think about it. It’s an observation of part of the Andromeda galaxy, taken with the Hubble Space Telescope, and the level of detail here is incredible. This image contains about 100-million stars that we can see in another galaxy. It’s just mind-blowing.

When we look at it, we start to be able to understand its structures. And what strikes me immediately is that it’s kind of familiar. If you zoom in on the spiral arm, it’s exactly the same as what we see when we look into our own Milky Way. And when we look at the Andromeda galaxy, we see this history, we see that it’s been cannibalizing these satellite galaxies in a similar way to the Milky Way, growing into this beast, this giant that’s a match for our own galaxy.

MICHELLE COLLINS: We now have many beautiful images of Andromeda. We studied it with a huge range of telescopes, and in many ways it’s a lot like the Milky Way, this beautiful spiral galaxy. So, you might think they are going to be very similar galaxies with a very similar history. But what we’ve learnt through studying Andromeda over time is that, actually, they are not quite the same.

NARRATOR: In fact, Andromeda is 50 percent bigger than the Milky Way. And that’s not all.

JEN GUPTA: The Andromeda galaxy is actually heading towards us, at about 250,000 miles per hour. In about four-and-a-half-billion years’ time, that faint smudge of light we saw in the sky will collide with the Milky Way galaxy, changing our galaxy forever.

NARRATOR: The Milky Way as we know it today, is not eternal. And Earth will witness the final act: two galaxies in a single sky, gradually, but inevitably, merging into one.

RANA EZZEDDINE: There is absolute evidence that Andromeda is going to collide with the Milky Way one day, because they are pulling each other closer and closer over time. And one day they will go so close that they will collide.

DAVID ROSARIO: Andromeda and the Milky Way, when they come together, sparks fly.

MICHELLE COLLINS: It’s going to be an incredible time. If we were able to view this collision happening, it would be amazing to watch the night sky change over time.

GERRY GILMORE: Be a really nice sight, actually. Yes, just watch it coming, I mean, there’s nothing you can do about it except sit back and enjoy the view.

MICHELLE COLLINS: We’ll end up smashing these two galaxies together. There may be a huge burst of star formation, initially, which will, sort of, light up the night sky with fireworks. And then, over time, that will burn off all the remaining gas we have in those two galaxies.

NARRATOR: But unlike in previous collisions, this time, our galaxy is the smaller of the two. Andromeda and the Milky Way pull at each other’s spiral arms, scattering stars, until no trace of the original structures remain, two spiral galaxies merged into one colossal mass of stars.

GRANT TREMBLAY: Watching the motion of galaxies is like looking at a really, really exquisite ballet in really, really slow motion. When that dance is finally complete, the structure of the Milky Way will be forever altered.

MICHELLE COLLINS: While this collision will extinguish the Milky Way and Andromeda as we know them, it will also create a whole host of new stars. And around those new stars, there’ll be new planets and maybe another generation of people asking the same questions that we’re asking now: Where have they come from? What’s their place in the galaxy? And what’s going to happen in their future?

DAVID ROSARIO: We will not be able to see the beautiful galaxy that we, that we see right now, but the universe will carry on.

NARRATOR: As we look even deeper into the future, all of the galaxies in our Local Group will eventually merge into one enormous entity, floating in isolation. As the universe expands, the distance between all the galactic groups will increase, and the other galaxies will simply disappear from view.

MICHELLE COLLINS: Knowing that we can, sort of, look into the future, many billions of years and understand what will happen to our galaxies is mind-blowing.

NARRATOR: And all of this, we have determined by looking up at the skies from one, tiny, unremarkable outpost in the Milky Way.

SOWNAK BOSE: Even though we, as humans, have such an insignificant role in the grand scheme of things, there is so much about the vastness of space that we can understand just from our unique perspective, here on Earth.

GRANT TREMBLAY: Earth is a tiny little rock and a really indescribably vast cosmic ocean, right? We are just a tiny little planet, spinning in the void.

NARRATOR: But the story of our night sky is far from being complete, and there is so much more to discover.

DAVID ROSARIO: Is there life in the universe? And has there been life in the universe from the very beginning?

RANA EZZEDDINE: What is dark matter? What is dark energy? How does it affect our universe? Particularly, how does it affect our Milky Way and even our own solar system?

NIA IMARA: We want to know where we come from, we want to understand our origins and our destiny. And also, we just love a good story. We love mystery. And the story of the universe is the greatest story of all.

Re: Caltech: The Mechanical Universe

by allynh » Fri Oct 29, 2021 6:40 pm

HA! I was thinking more along the lines that they show the early universe filled with blue giants rather than a mix of every size star. And the obvious question is, How do they know?

Then they talk about the blue giants exploding and spreading newly created elements everywhere to form other stars. Well, why didn't those stars create "black holes". That's what is supposed to happen when a star beyond a certain mass is supposed to create. At least, that's what they say in other programs discussing nonexistent black holes.

Plus, when the star exploded it scattered all of its atoms everywhere. How was gravity supposed to pull everything back together into a proto solar system.

The main problem I have with the computer imagery is that they are showing thick clouds when space is essentially a vacuum. How did rocks form out of gas to then smash together and form a planet, etc...

We would need to go minute by minute through the video, asking how they know what they are saying, and why are they missing such obvious things like the fact that "Dark matter" has never been shown to exist.

They have all those great computer graphics showing faint structures as if the human eye could see them, yet when they show the Sun they don't show the vast unseen electrical structures that is actually powering it.

Read the Bethe paper on the Sun that I have up thread and you will see that he simply made up how "fusion" in the core powers the Sun.

The only thing in the whole program that was "fact based" is the Parker Solar Probe, yet the computer imagery of it is pure fantasy.

Re: Caltech: The Mechanical Universe

by jacmac » Fri Oct 29, 2021 2:11 am

PAYEL DAS (University of Surrey): If we understand where the sun comes from, we can understand a little bit more about where life has come from.
The sun comes from the abundance of plasma in the universe, AND
the ability of the plasma to self organize
EMMA CHAPMAN: The sun is still full of mysteries. Why is it hotter in its atmosphere than on its surface?
The trapped plasma inside the chromosphere double layer (DL) rises , then gets turned back,,,,,,
disappointed hot, but not angry hot.
The incoming charged particles are moving fast and want to join the action.
The chromosphere lets some in and some not.
Those that get in are orderly, happy to march in line, keeping the temperature low.
Those kept out are not happy, turning about in all manner of ways interfering with each other and the newer arrivals.
all hell breaking loose; thus the temperature soars.
RAMAN PRINJA: We can actually see cells of hot gas rising and falling into incredible imagery.

GIBOR BASRI: And then, above that, you have this very thin atmosphere that’s a million degrees, super hot.

EMMA CHAPMAN: Seeing these images is like revealing something that’s been right in front of us but hidden, for so long.
Well....er.... never mind.
NARRATOR: The cosmic web is unimaginable in scale. Huge clouds of gas are drawn together by the gravityof a mysterious, invisible form of matter, called “dark matter,” creating a great network offilaments, a web the size of the cosmos.
The web IS the cosmos actually.
-----
-----
-----
-----
-----
-----
Yadda, Yadda, Yadda.....
NARRATOR: The Parker Solar Probe is spotting holes in the sun’s atmosphere, vents that release a blizzard ofcharged particles, at more than a million miles an hour, what we call the “solar wind.”
NARRATOR: The solar wind travels billions of miles, bombarding the planets with radiation.
WOW.....could you tell that to the climate guys please !
primitivecells, living in the ocean,
the “Goldilocks” zone.
“photosynthesis,”
up to 400-billion stars in our galaxy,
13.8-billion years
“tidallylocked”
the age of stellar creation in the universe is waning.
A cosmos eventually defined more by darkness than by light.
We live in the Age of Stars.
Oh no !......it's a bad ending.
But I liked the beginning.

NOVA The Universe: Age of Stars

by allynh » Thu Oct 28, 2021 4:38 pm

This episode of NOVA was on last night, and it was deeply disturbing to watch the modern day fantasy of Scientism. I would like to see the whole episode be "Fact Checked", point by point.

What was interesting, is that they did not start with the big bang, or even mention black holes but they do mention neutron stars.

They mention plasma but focus of dark matter and gravity to explain everything.

This nihilistic view of reality is what they are pushing now.

BTW, the episode reminded me the most of the Lord Kelvin papers about the Sun that I mentioned up thread. Having the universe fade into darkness is exactly what Lord Kelvin was saying would happen when the Sun goes dark.

We've come full circle back to Lord Kelvin.

The Universe: Age of Stars
https://www.pbs.org/wgbh/nova/video/nov ... -of-stars/
PREMIERED OCTOBER 27, 2021 AT 7PM ON PBS
The sun is our life-giving source of light, heat, and energy, and new discoveries are unraveling its epic history. Join NOVA on a spectacular voyage to discover the sun’s place in a grand cycle of birth, death and renewal that makes this the age of stars. Witness how stars of every size and color came to populate our universe; how stars stage a dramatic exit when they explode as supernovae, which can outshine an entire galaxy; and how, billions of years in the future, the age of stars will lead ultimately to an age of darkness. (Premiered October 27, 2021)

TRANSCRIPT
The Universe: Age of Stars

PBS Airdate: October 27, 2021

NARRATOR: In a universe that shines with innumerable stars, born from countless more stars that have come and gone before them, rages the life-giving fire of our sun.

GIBOR BASRI (University of California, Berkeley): The sun is the king of the solar system. It has, essentially, all the mass and all the energy.

NARRATOR: Familiar and yet unknown.

EMMA CHAPMAN (Imperial College London): Even though we’ve looked at it for a really long time, the sun is still full of mysteries. Why is it hotter in its atmosphere than on its surface? What drives the solar wind?

NARRATOR: Only now, we take our first steps closer to understanding our star.

KELLY KORRECK (Co-Investigator, Parker Solar Probe): It’s the first time that we’re actually going in to touch the sun.

GRANT TREMBLAY (Center for Astrophysics | Harvard & Smithsonian): And it’s already really started to truly transform our understanding for how the sun works.

NARRATOR: Uncovering the secret power of all stars….

RANA EZZEDINE (University of Florida): As you can imagine, when you have a huge blob of flaming gas, the coreis usually the hottest, and it is where the magic is happening.

NARRATOR: …perhaps even finding clues to the stars that came before it…

PAYEL DAS (University of Surrey): If we understand where the sun comes from, we can understand a little bit moreabout where life has come from.

NARRATOR: …and, ultimately, its fate.

RAMAN PRINJA (University College London): It has about another 4.6-billion years of nuclear fusion left. And thenit will start to change. It will start to evolve.

GHINA M. HALABI (University of Cambridge): We really need to understand what will happen to our own sun,because that will impact Earth.

NARRATOR: The sun is just one among hundreds of billions of stars, in a galaxy among trillions. We live in theAge of Stars, right now, on NOVA.

Ninety-three-million miles from Earth, our nearest star: the sun, a permanent fixture for life onour planet.

KELLY KORRECK: Humans have always been fascinated by the sun, I think, because it is so constant, compared toour daily life.

NIA IMARA (Center for Astrophysics | Harvard & Smithsonian): It’s been rising and setting since the day that wewere born. We keep time by it. We keep our calendars by it. Without it, life wouldn’t be possible,here on Earth.

NARRATOR: The sun is just one of more than a billion-trillion stars in the universe. Why is it around our starthat life has emerged?

ANJALI TRIPATHI (Center for Astrophysics | Harvard & Smithsonian): We want to know, “Where do we comefrom?” And, “What are our cosmic origins?”

PAYEL DAS: If we understand where the sun comes from, we can understand a little bit more about where lifehas come from.

NARRATOR: But our star is an enigma.

EMMA CHAPMAN: The sun is still full of mysteries. Why is it hotter in its atmosphere than on its surface? Whatdrives the solar wind?

NARRATOR: We’ve spent millennia studying from afar, but only now are we getting close enough to trulyreveal its secrets.

RAMAN PRINJA: The sun’s not a very nice environment. It’s not easy to get up close to the sun.

GIBOR BASRI: It’s an enormous ball of hydrogen, and it’s putting out a tremendous amount of energy.

NARRATOR: Its surface is a bubbling cauldron of 10,000-degree plasma.

RAMAN PRINJA: We can actually see cells of hot gas rising and falling into incredible imagery.

GIBOR BASRI: And then, above that, you have this very thin atmosphere that’s a million degrees, super hot.

EMMA CHAPMAN: Seeing these images is like revealing something that’s been right in front of us but hidden, for solong.

RAMAN PRINJA: Occasionally, you might see this enormous coronal mass ejection erupting from the star.

NARRATOR: We now stand on the threshold of being able to survive a close encounter, with a new heat-resistant probe that’s giving us an up-close look at our sun, for the first time.

MISSION CONTROL: Status check. Do delta. Go P.S.P.

T minus 15.

KELLY KORRECK: Launch night, I was sick to my stomach.

MISSION CONTROL: Five, four, three, two, one, liftoff of the Might Delta IV Heavy rocket, with NASA’s ParkerSolar Probe. And there we go.

KELLY KORRECK: The Delta IV Heavy is a very slow rocket compared to the other launches I’ve seen. So, I justsaw fireballs and was very, very frightened for a while.

MISSION CONTROL: Twenty-five seconds into flight.

CHRIS CHEN (Queen Mary University of London): It is quite scary to think about all that power in the rocket,underneath that, you know, relatively small spacecraft sitting on top.

KELLY KORRECK: Then realizing that this was all okay, as it slowly made its way up into the sky.

MISSION CONTROL: Fifty seconds into flight.

KELLY KORRECK: And then just watched it…

MISSION CONTROL: Ejecting strap on boosters.

GRANT TREMBLAY: Parker is just an exquisite mission. It will be the closest that our species has thus far come to,literally, touching the sun, itself.

NARRATOR: The Parker Solar Probe is travelling to a place that has been completely unexplored up close, until now.

ARCHIVE: NASA’s Parker Solar Probe: a daring mission to shed light on the mysteries of our closest star.

EUGENE PARKER: This is a journey into never-never land, you might say.

NARRATOR: During its seven-year mission, the Parker Solar Probe will attempt a series of dives towards thesurface of the sun. Its goal is to understand how the sun sheds its energy. Orbiting a total of 24times, each pass taking it perilously closer, so close, it will enter the sun’s atmosphere, bravingtemperatures no spacecraft has ever endured and travelling faster than any other human-madeobject has before.

The mission is still in its early days, but in the coming years, the Parker Solar Probe will help usunlock, not only the secrets of our own sun, but all stars, including those that hold the key to thesun’s origins and our own.

EMMA CHAPMAN: We can look at the processes, look at what’s inside the sun, and understand how it had tobecome that. What were the generations of stars before that? What was its ancestry?

NARRATOR: The sun’s story can be traced back to its most distant stellar ancestors, the very first stars in theuniverse. Almost 100-million years after the Big Bang, the universe is dark and cold, not a singlestar shining. But this universe is far from empty. Something is growing in the void, stretching outtendrils.

ANJALI TRIPATHI: The early universe was largely hydrogen and helium and only small amounts of other materials.

GHINA HALABI: None of the elements we see these days, no carbon, oxygen, iron, none of that.

SOWNAK BOSE (Center for Astrophysics | Harvard & Smithsonian): Even though the name the “Cosmic Dark Ages”suggests that there might not have been anything particularly interesting going on, it was really,kind of, laying the groundwork for the construction of the cosmic web.

GRANT TREMBLAY: The cosmic web is, literally, the structure of the universe itself.

NARRATOR: The cosmic web is unimaginable in scale. Huge clouds of gas are drawn together by the gravityof a mysterious, invisible form of matter, called “dark matter,” creating a great network offilaments, a web the size of the cosmos.

The gas in these tendrils is made up of mostly hydrogen and helium. Where these great filamentscross, are the places where the first stars will one day be born.

The cosmic web has been shaping our universe for 13.8-billion years, and it’s still doing sotoday. But it’s only recently that we’ve actually been able to see it.

PAYEL DAS: The image that we have here is absolutely amazing. It’s one of the most fundamental pictures thatwe can take in our universe. And it’s actually a direct image of some of the largest structures thatexist, the filaments of the cosmic web. Now, the bright white dots that you see over here, they’reentire galaxies. Now, if I take those away, what you can see much more clearly is the faint glowof the hydrogen and helium that exists on the tendrils of the cosmic web. And it’s on this cosmic web that the story of our sun and the stars in our night sky begins.

NARRATOR: As time passes in the early universe, the cosmic web continues to grow. Gas, rushing along thesegreat tendrils, travelling down towards the intersections…it is being pulled to these points bygravity. And as more gas joins, this force becomes ever stronger, creating great clouds,staggering in size.

They grow denser, hotter, as gas is relentlessly added, until, at last, the conditions become soextreme that there is a sudden moment of ignition: the birth of the very first star in the universe, born 17-times hotter than the sun. This star is a “blue monster.”

EMMA CHAPMAN: The first stars were unlike anything we can see around us today, which is what makes them soincredible.

COURTNEY DRESSING (University of California, Berkeley): When the very first stars formed, these stars ended upwith giant masses of 500- to 600-times the mass of the sun.

GIBOR BASRI: Stars today are perhaps as hot as 100,000 degrees, and these stars were nearly twice as hot asthat. The very hot color tends to also make them look blue.

NARRATOR: But this first star is not alone for long. At intersections across the cosmic web, it’s soon joined byothers, an entire generation of first stars, lighting up the universe.

But this isn’t all they do. These stars are forging new elements, creating the ingredients for all theplanets and, ultimately, even for life to exist.

PAYEL DAS: The birth of the first stars signaled a complete transformation in the makeup of the universe. Before they existed, all we had was hydrogen and helium, but nuclear fusion completely changedall of that.

NARRATOR: The cores of the first stars were so hot, they reached more than 100-million degrees. And thatforced hydrogen atoms to change.

PAYEL DAS: Now, under the very high temperatures and pressures that you find in the core of these stars, theywere smashed together, fusing a heavier element, helium.

NARRATOR: But the first stars didn’t stop there.

PAYEL DAS: After a few million years, the hydrogen completely runs out. So, instead, the helium atoms areforced to be smashed together, creating even heavier elements, elements such as carbon, oxygenand iron.

NARRATOR: The new elements these first stars forged are the elements that seed other types of stars, planetsand even us, in other words, the elements for life.

But the era of blue giants can’t last…

ANJALI TRIPATHI: Fusion at the center of a star eventually ends, as it runs out of fuel, so the process can’t go onforever.

EMMA CHAPMAN: When fusion stops, you lose that internal pressure which pushes against gravity. You lose a tug-of-war, and the gravity starts to push down on the star.

GRANT TREMBLAY: You know that, that saying, “Live fast, die young?” That, that really applies to stars, right?And so the most massive luminous stars have the shortest lifetimes.

NIA IMARA: Even though they have much more hydrogen fuel than an ordinary star like our sun, they burn itso quickly that they only live a few million years before they burn out. In a few million years, inastronomy time, that’s the blink of an eye.

NARRATOR: With its fuel spent, fusion reactions stop and gravity takes over. The core collapses. Gas suddenlyfalls inwards and then rebounds in a colossal explosion, called a “supernova,” a shockwave ofenergy followed by material hurtling outwards into space.

RAMAN PRINJA: Supernovae explosions rocked the universe. They are amongst the most explosive events that wenow know about. Briefly, a single supernova can outshine an entire galaxy.

RANA EZZEDDINE: This was a very important moment in the history of the universe. It allowed the universe to,kind of, start evolving.

GHINA HALABI: After the first stars exploded, the material that has been forged in their interiors was spewn outinto space.

NIA IMARA: They seeded the universe with these heavy elements and paved the way for subsequentgenerations of stars.

NARRATOR: Generations of stars that we can see in the night sky. The Hubble Space Telescope has beenstudying them for more than 30 years, showing us this epic cycle of cosmic death and renewal.

EMMA CHAPMAN: It’s not only the first stars which enriched the universe. As you go on for the second, the third,the fourth generation of stars, they’re all creating more and more heavy elements which getexpelled into the universe.

NARRATOR: Hubble reveals to us how stars have evolved, from a primitive universe dominated by blue stars, to our universe today, populated by stars of every color, size and configuration: neutron stars,violently spinning up to 700 times a second, spitting out jets of radiation; stars so huge that morethan a billion suns could fit inside them.

COURTNEY DRESSING: There are many types of stars, Wolf-Rayet stars, red giant stars, white dwarf stars. All ofthem have their own unique characteristics.

NARRATOR: And some that aren’t alone. They are kept company by systems of planets, including rocky worldsbuilt of ingredients like carbon, silicon and iron.

GRANT TREMBLAY: So, stars really are the engines of higher order complexity in the universe. They’re thefactories that make up the heavier elements that are the seeds of things like planets.

NARRATOR: Stars have changed the entirety of the universe, filling it with all manner of wondrous celestialobjects and, ultimately, paving the way for a star that has all the right conditions to make us.

RAMAN PRINJA: The sun must have relied on many, many generations of previous stars for the material that’sthere today in our solar system, probably thousands of other stars that would have had to explode.

NARRATOR: Nine-billion years after the birth of the first star, the universe has been enriched with dozens ofnew elements. Here, gravity draws one cloud together, and our own star is born.

But not all of the material is used to create the sun. Some remains in orbit. And it’s from theseleftovers that eight extraordinary planets form: our solar system.

RAMAN PRINJA: The sun has a very tight relationship with all the planets in the solar system, not just because ofits enormous gravity, but because of the light that it provides.

NARRATOR: Some of these worlds seem just too far away from the sun for complex life to take hold. Deprivedof light, they may be devoid of any life at all. These are the gas and ice giants. In contrast, othersare too close to the sun. They are relentlessly blasted, until they become scorched deserts. Butthere is a sweet spot, neither too far, nor too close to the sun. It’s in this place that the chemicallegacy of generations of long-gone stars would form something astonishing.

KELLY KORRECK: We are, on the earth, on kind of this special sweet zone. They call it the “Goldilocks” zone.

PHILIP MUIRHEAD (Boston University): This exciting distance from a star, where a planet could conceivably haveliquid water on its surface.

GHINA HALABI: Water is the medium that facilitates the biochemical reactions that are responsible for life.

EMMA CHAPMAN: Earth’s relationship with the sun is the most important relationship there is.

NARRATOR: The sun is constantly reaching out to our planet, something the Parker Solar Probe is helping usunderstand.

KELLY KORRECK: What makes Parker so great is the fact that it has a great set of instruments that work together inorder to look in all directions.

GRANT TREMBLAY: So, there’s this sun-facing part of the probe that peaks above the heat shield and, literally,looks directly at the sun.

NARRATOR: The Parker Solar Probe is spotting holes in the sun’s atmosphere, vents that release a blizzard ofcharged particles, at more than a million miles an hour, what we call the “solar wind.”

KELLY KORRECK: We can tell how the energy flows, where the wind is coming off, how much of the wind iscoming off.

NARRATOR: The solar wind travels billions of miles, bombarding the planets with radiation.

COURTNEY DRESSING: The charged particles in the solar wind can be detrimental to life. On Earth, we’reprotected by the Earth’s magnetic field, which deflects the particles.

GIBOR BASRI: So, it’s kind of like we have our shields up, and our shield is our magnetic field.

NARRATOR: Earth has defenses that protect life from our star’s violent tendencies, but the sun also providessomething essential to our planet.

RANA EZZEDDINE: At the core of the of it, the sun is forging hydrogen into helium, which is what is releasing theenergy that we see or that we get here on Earth.

GHINA HALABI: The photons, these packets of energy, when they are formed, they don’t go straight from thecenter, rushing through to the surface. They go through a very bumpy ride. They get tossed fromone atom to the other. They get absorbed and spit out, absorbed and spit out.

EMMA CHAPMAN: So, it takes a really convoluted path out of that sun, and that can take millions of years.

NARRATOR: Once these photons arrive at the surface, they’re liberated as sunshine. The light races across thesolar system. Unobstructed, it flashes past the planets at 180,000 miles per second.

GIBOR BASRI: If you could take all the energy that humans are producing and store it in batteries, the entirecivilization, for 50,000 years, you could make the sun shine for one second.

NARRATOR: It takes just over eight minutes for the sun’s light to reach Earth.

LUCIE GREEN (University College London): That stream of light is like an umbilical cord of energy, coming downto us, here on Earth. And it has been pretty much constant and unbroken for nearly five-billionyears.

And it’s this combination of the stability of light, stability of energy, over billions of years, thatmeans complex life that we see around us, here on the earth, has been able to form and has beenable to thrive.

NARRATOR: We don’t know exactly how life emerges on early Earth, but what we do know is that primitivecells, living in the ocean, begin to use the sun’s energy to power life-giving chemical reactions.

These cells are the bridge between sun and Earth, tiny machines that harness the power of ourstar. The cells use sunlight to turn carbon dioxide and water into food in the form of sugar.

This process, “photosynthesis,” is a direct use of the sun’s power. It has driven the evolution ofcomplexity on Earth, from primitive bacteria, to plants and trees, an unbroken line of livingthings, all connected to the power source in the sky.

GHINA HALABI: Everything, from the little blade of grass to the biggest oak tree, they use the sunlight tophotosynthesize and produce the energy that we later consume to sustain ourselves. So, in a way,we have been feeding on starlight.

NARRATOR: Trillions of stars have existed since the universe began, but ours is the only one we know of thathas nurtured that wonderful thing, life, not only nourished by the sun’s light, but also grantedprotection and the time to grow and change, eventually creating complex life.

NIA IMARA: The sun is connected to our very existence. It provides the light and the energy that’s necessary tosustain life.

GRANT TREMBLAY: There would absolutely be no life on Earth if there was no sun.

NARRATOR: The sun is a creator, bringing together atoms forged in generations of ancient stars, to create us: beings capable of exploring the cosmos, and uncovering our own stellar ancestry.

GHINA HALABI: It’s a wonderful thing how we share this intimate connection with stars, because they are part ofour cosmic heritage. We are the children of these stars.

NARRATOR: There are up to 400-billion stars in our galaxy, and there are two-trillion galaxies in ouruniverse. But it wasn’t always that way. We are living in the age of stars, an era of light in theuniverse.

GHINA HALABI: Stars have always been important to us. They have helped us navigate the land and the open seasfor millennia.

SONAK BOSE: If you just think back at the countless sonnets and poems and songs, there is always some kind ofcelestial connection.

NIA IMARA: One of the reasons why looking up into the stars is so significant is because we realize that othersare doing the same exact thing. And so, in a very real way, we feel connected to, to people both,both past and present.

NARRATOR: From our fleeting human perspective, the stars seem everlasting, a constant in our night sky. Butseen across the age of the universe, the picture changes, because this era cannot last. The starswill eventually wane. And as they go, they once again change the character of the universe. Theircores, where fusion once raged, cool and eventually solidify, locking precious elements away,beneath the surface, and starving the universe of the material needed to make new stars andplanets.

GRANT TREMBLAY: The chance that a star is going to be born nowadays is, is much, much lower than it was,billions of years in the past.

RAMAN PRINJA: Just as there was a very first star in the universe, there will come a time when the era of stars willcome to an end.

NARRATOR: The age of stars is not as enduring as it might seem.

LUCIE GREEN: I have a timeline of the universe, and I’m here, at the start, when the universe formed 13.8-billion years ago, during the Big Bang. Now, it took a while for the first stars to form, in fact, afew hundred million years. Let’s call that 400-million years. So, on my scale, stars start to formhere. And those stars carried on forming, and then we reach this point, four-billion years sincethe Big Bang and a time when the most stars are forming in the universe. Our sun, though, didn’tform until nine-billion years had passed. And that’s my marker here.

And then we move forwards again, and we get to this point, here, which is the present day, 13.8-billion years since the formation of the universe.

Now, our sun won’t live forever, and, in fact, it will start to die and end its life in around five-billion years’ time. But the sun will be outlived by the least massive stars in the universe. Theyhave lifetimes of a few hundred billion years and that’s about 200 meters on my scale. But evenwhen those stars die, that doesn’t mark the end of the universe. The universe could live forever,with the timeline stretching far off into the distance. And that means that the age of starlight thatI’ve mapped out here is like the blink of an eye to the universe. It’s the age of darkness that goeson and on and on.

NARRATOR: Stars won’t suddenly disappear of course, they’ll be here for hundreds of billions, perhaps eventrillions of years to come.

But slowly, over time, the universe will become darker, emptier. As it expands, the distancesbetween these little islands of light become greater and greater, until, one day, only one type ofstar will remain: red dwarfs, the longest lived of all stars in the universe.

Trappist 1 is one of these near immortals. This ancient star is likely more than seven-billionyears old, almost twice as old as our Sun. But Trappist is tiny: a similar size to Jupiter and lessthan one percent as bright as our sun. It is a cool star, slow-burning. And that is the secret of itslongevity.

DAVID CHARBONNEAU (Center for Astrophysics | Harvard & Smithsonian): The lifetime of a star is determined byits reservoir of hydrogen, of nuclear fuel. As long as it has something to burn, it will continue tosurvive. But, paradoxically, the stars with the least amount of hydrogen live the longest. Andthat’s because they are miserly. They spend their fuel so slowly.

GRANT TREMBLAY: And so it’s those smaller, more quiescent, less energetic stars that, ultimately, become thegreatest historians of the universe.

PHILIP MUIRHEAD: It’s especially exciting, because this particular star is going to continue fusing hydrogen intohelium in its core and continue shining for, potentially, hundreds of billions of years.

NARRATOR: Like the sun, Trappist has its own planets, seven worlds, each roughly the size of Earth. Somemay have atmospheres and even oceans, but there the similarities end, because these are strangeworlds.

Just as one side of the moon always faces Earth, these planets may be what we call “tidallylocked” in their orbits. One side permanently looking towards the red dwarf Trappist 1, soakingup what light and warmth it can from the faint star, the other side permanently frozen, facing thecold void of space.

These planets are witnesses to much of the life of the universe. They were born near the start andthey will survive to near the end of the age of stars.

They will see entire galaxies merge and eventually begin to fade in their night skies. They watchas countless stars come and go, bearing witness to the time, about five-billion years from now,when a distant star begins to fade and vanishes from the night sky as our sun finally exhausts itsfuel and disappears forever.

NIA IMARA: Ultimately, once the fusion process is over in the sun, it will begin to expand into whatastronomers call a “red giant.” And the outer envelope of the sun will expand.

RANA EZZEDDINE: It’s going to gulp up some of the planets around it. Unfortunately, Earth is one of them.

NARRATOR: And as the sun dies, so too will many others like it.

The age of stellar creation in the universe is waning.

GRANT TREMBLAY: The universe is like a slow-motion fireworks show and we’re kind of watching the end of it.

NARRATOR: It’s unlikely that Trappist 1 will be the very last star in the universe, but we do believe the laststar will be a red dwarf. As its fuel runs out, fusion comes to an end. The last star slowly coolsand fades away.

With its passing, the universe becomes cold and dark, without light, and, most likely, without life.

RAMAN PRINJA: When the last red dwarf stars die out, that will be the end of stars in the universe. And it wasstarlight that really lit up its story.

NARRATOR: A universe without light may be unfathomable to us humans. Stars made us and our planet. Theydefine the universe, as we know it, today.

GHINA HALABI: It was like a gift given to humanity that it took a cosmos to make you.

NARRATOR: A cosmos eventually defined more by darkness than by light. But for now, we exist and learn andgrow, as tiny sparks, within the bright and light-filled childhood of our universe.

We live in the Age of Stars.

Re: Caltech: The Mechanical Universe

by allynh » Tue Aug 24, 2021 9:46 pm

This is another book that has it backwards, claiming that the "discovery" of the "background radiation" proved the big-bang theory was right and Hoyle's "Steady State" was wrong.

Hoyle was right, The "consensus" was wrong.

When the Big Bang Was Just a Theory
https://www.nytimes.com/2021/08/24/book ... lpern.html
Aug. 24, 2021, 5:00 a.m. ET
Nonfiction

From left: George Gamow in 1961 and Fred Hoyle in 1958. At midcentury, the two engaged in a spirited debate about the origins of the universe.
From left: George Gamow in 1961 and Fred Hoyle in 1958. At midcentury, the two engaged in a spirited debate about the origins of the universe.Associated Press; Evening Standard/Getty Images
When you purchase an independently reviewed book through our site, we earn an affiliate commission.

FLASHES OF CREATION
George Gamow, Fred Hoyle, and the Great Big Bang Debate
By Paul Halpern

The universe is changing. But scientists didn’t realize that a century ago, when astronomers like Edwin Hubble and Henrietta Leavitt discerned that other galaxies exist and that they’re hurtling away from the Milky Way at incredible speeds. That monumental discovery sparked decades of epic debates about the vastness and origins of the universe, and they involved a clash of titans, the Russian-American nuclear physicist George Gamow and the British astrophysicist Fred Hoyle.

In his new book, “Flashes of Creation,” Paul Halpern chronicles the rise of Gamow and Hoyle into leaders of mostly opposing views of cosmology, as they disputed whether everything began with a Big Bang billions of years ago.

Halpern, a physicist himself at the University of the Sciences in Philadelphia, skillfully brings their fascinating stories to light, out of the shadow of the overlapping quantum physics debates between Albert Einstein and Niels Bohr, which Halpern has written about in an earlier book. Halpern also poses fundamental questions about how science should be done. When do you decide, for example, to abandon a theory? Ultimately, his book seeks to vindicate Hoyle, who in his later years failed to admit his idea had lost.

Until these two bold theoreticians arrived, astrophysics had been stuck at an impasse. Scientists weren’t sure how to interpret Hubble’s observations, and no one understood how the universe created and built up chemical elements. “It is clear that the intuitive, seat-of-the-pants styles shared by Gamow and Hoyle were absolutely needed in their time,” Halpern writes.

Gamow and Hoyle make for a challenging “joint biography,” Halpern acknowledges, in part because their parallel stories so rarely intersected. They had only one significant in-person meeting, in the summer of 1956 in La Jolla, Calif., where Gamow had briefly served as a consultant for General Dynamics, the aerospace and defense company. They discussed many ideas in that coastal town, hanging out in Gamow’s white Cadillac, but for the most part, their debates took place in the pages of physics journals, newspapers and magazines, including Scientific American.

They also frequently appeared on early television and radio programs, becoming among the first well-known science communicators, paving the way for Carl Sagan, Neil deGrasse Tyson, Bill Nye, Carolyn Porco, Pamela Gay and others today. Hoyle wrote the science fiction novel “The Black Cloud” and the television screenplay “A for Andromeda,” while Gamow produced “One, Two, Three … Infinity” and the Mr. Tompkins series, whose main character’s predicaments illustrated aspects of modern science.

For years, their dueling theories — a Big Bang origin of matter and energy (championed by Gamow) versus a steady-state universe that created matter and energy through quantum fluctuations (championed by Hoyle) — remained highly speculative. Initially, the Big Bang theory predicted a universe only a couple billion years old, which conflicted with observations of the sun and other stars, known to be much older. Physicists were evenly divided between the two.

But that changed as more evidence emerged, and a key discovery eventually seemed to settle the debate. In 1964, the astronomers Arno Penzias and Robert Wilson noticed a constant signal of radio static with the Holmdel Horn Antenna in New Jersey. After ruling out possible experimental sources of noise (including pigeons and their droppings on the antenna), they deduced that the radio hiss had a cosmic origin. They and their colleagues eventually realized the signal came from relic radiation from the hot fireball of the early universe.

Paul HalpernUniversity of the Sciences

After that, the Big Bang theory quickly became consensus in the field. While Hoyle’s steady-state idea eventually failed, he made many other significant contributions, especially involving stellar processes and supernova explosions, which he showed could fuse chemical elements into heavier atoms and produce nitrogen, oxygen, carbon and more. In explaining this, and throughout the book, Halpern provides many helpful metaphors and analogies. He also reminds readers that Hoyle, Gamow and their fellow theoretical physicists made these accomplishments well before the heyday of supercomputers.

Halpern doesn’t shy away from the characters’ flaws. In particular, he shows how Hoyle’s work later in life lay on the fringes of physics, including his controversial “panspermia” hypothesis, that organic material and even life on Earth came from colliding comets, and his unsuccessful attempts to revive steady-state theory. But this shouldn’t cast a pall over his legacy.

Hoyle’s investment in the theory raises important philosophical and sociological questions about when we should consider an idea proven. It’s also the sort of quandary that threads its away through contemporary debates among physicists: about dark matter versus modified gravity theories; about what dark energy is and how the universe’s “inflation” happened moments after the Big Bang; and about a persistent discrepancy in measurements of the universe’s expansion rate, known as the “Hubble tension.” Halpern unfortunately gives only brief mention to these active areas of research, which owe a lot to Gamow and Hoyle.

At one point in the book, Halpern relates a conversation he had with Geoff Burbidge, a colleague of Hoyle’s who also continued to support a steady-state model. Cosmology needed alternatives, he argued, not lemmings following their leader over a cliff.

Re: Caltech: The Mechanical Universe

by allynh » Tue Jul 20, 2021 6:01 pm

In Forum 2.0 I talked about a lecture replacing Feynman diagrams with the Amplituhedron.

Re: Caltech: The Mechanical Universe
https://www.thunderbolts.info/forum/php ... 11#p128523
wiki - Amplituhedron wrote: Implications

The twistor approach simplifies calculations of particle interactions. In a conventional perturbative approach to quantum field theory, such interactions may require the calculation of thousands of Feynman diagrams, most describing off-shell "virtual" particles which have no directly observable existence. In contrast, twistor theory provides an approach in which scattering amplitudes can be computed in a way that yields much simpler expressions. Amplituhedron theory calculates scattering amplitudes without referring to such virtual particles. This undermines the case for even a transient, unobservable existence for such virtual particles.

The geometric nature of the theory suggests in turn that the nature of the universe, in both classical relativistic spacetime and quantum mechanics, may be described with geometry.

Calculations can be done without assuming the quantum mechanical properties of locality and unitarity. In amplituhedron theory, locality and unitarity arise as a direct consequence of positivity. They are encoded in the positive geometry of the amplituhedron, via the singularity structure of the integrand for scattering amplitudes. Arkani-Hamed suggests this is why amplituhedron theory simplifies scattering-amplitude calculations: in the Feynman-diagrams approach, locality is manifest, whereas in the amplituhedron approach, it is implicit.

Since the planar limit of the N = 4 supersymmetric Yang–Mills theory is a toy theory that does not describe the real world, the relevance of this technique for more realistic quantum field theories is currently unknown, but it provides promising directions for research into theories about the real world.
I did not realize that the concept destroys the concept of the "Inflationary" universe that Lawrence Krauss talks about in his book.

wiki - A Universe from Nothing

I stumbled on this Colbert Report episode on YouTube.

STEPHEN COLBERT HUMILIATES LAWRENCE KRAUSS
https://www.youtube.com/watch?v=tXK5avcaJiY

Krauss points out many times that his "Nothing" is actually space filled with "virtual particles" which is why space is expanding at high speed.

"Virtual particles" are an "artifact" of the Feynman diagrams. They only exist on paper, they do not exist in reality.

Re: Caltech: The Mechanical Universe

by crawler » Fri Jul 10, 2020 1:28 am

The streamlines of aether flowing into a star converge in 3 dimensions hencely the aether acceleration relates to 1/rr & hencely gravity relates to 1/rr.

The 1/r behavior of orbiting stars in flattish spiral galaxies is what u would expect in a disc shape. In a disc galaxy the aether in the near field in effect converges in 2 dimensions not 3, giving a 1/r aether acceleration, hencely a 1/r gravity. No dark matter needed.

And i suppose that the spiral arms are leaning/curving forward because gravity has a finite speed (do they lean/curve forward??)(if they lean back then i am wrong).

Does dark matter exist?

by allynh » Thu Jul 02, 2020 2:50 am

This is another example of how a "narrative" develops from nothing to define reality. If you read the article and the supporting documents, all the while knowing that the answer is "No", because they ignored electricity, then you will have a better understanding of how far people will go to create a "narrative".

It is important to see what consensus "beLIEves".

Does dark matter exist?
https://aeon.co/essays/why-its-time-to- ... -seriously
Dark matter is the most ubiquitous thing physicists have never found: it’s time to consider alternative explanations

Ramin Skibba25 June, 2020

In 1969, the American astronomer Vera Rubin puzzled over her observations of the sprawling Andromeda Galaxy, the Milky Way’s biggest neighbour. As she mapped out the rotating spiral arms of stars through spectra carefully measured at the Kitt Peak National Observatory and the Lowell Observatory, both in Arizona, she noticed something strange: the stars in the galaxy’s outskirts seemed to be orbiting far too fast. So fast that she’d expect them to escape Andromeda and fling out into the heavens beyond. Yet the whirling stars stayed in place.

Rubin’s research, which she expanded to dozens of other spiral galaxies, led to a dramatic dilemma: either there was much more matter out there, dark and hidden from sight but holding the galaxies together with its gravitational pull, or gravity somehow works very differently on the vast scale of a galaxy than scientists previously thought.

Her influential discovery never earned Rubin a Nobel Prize, but scientists began looking for signs of dark matter everywhere, around stars and gas clouds and among the largest structures in the galaxies in the Universe. By the 1970s, the astrophysicist Simon White at the University of Cambridge argued that he could explain the conglomerations of galaxies with a model in which most of the Universe’s matter is dark, far outnumbering all the atoms in all the stars in the sky. In the following decade, White and others built on that research by simulating the dynamics of hypothetical dark matter particles on the not-so-userfriendly computers of the day.

But despite those advances, over the past half century, no one has ever directly detected a single particle of dark matter. Over and over again, dark matter has resisted being pinned down, like a fleeting shadow in the woods. Every time physicists have searched for dark matter particles with powerful and sensitive experiments in abandoned mines and in Antarctica, and whenever they’ve tried to produce them in particle accelerators, they’ve come back empty-handed. For a while, physicists hoped to find a theoretical type of matter called weakly interacting massive particles (WIMPs), but searches for them have repeatedly turned up nothing.

With the WIMP candidacy all but dead, dark matter is apparently the most ubiquitous thing physicists have never found. And as long as it’s not found, it’s still possible that there is no dark matter at all. An alternative remains: instead of huge amounts of hidden matter, some mysterious aspect of gravity could be warping the cosmos instead.

The notion that gravity behaves differently on large scales has been relegated to the fringe since Rubin’s and White’s heyday in the 1970s. But now it’s time to consider the possibility. Scientists and research teams should be encouraged to pursue alternatives to dark matter. Conferences and grant committees should allow physicists to hash out these theories and design new experiments. Regardless of who turns out to be right, such research on alternatives ultimately helps to crystallise the demarcation between what we don’t know and what we do. It will encourage challenging questions, spur reproducibility studies, poke holes in weak spots of the theories, and inspire new thinking about the way forward. And it will force us to decide what kinds of evidence we need to believe in something we cannot see.

We have been here before. In the early 1980s, the Israeli physicist Mordehai ‘Moti’ Milgrom questioned the increasingly popular dark matter narrative. While working at an institute south of Tel Aviv, he studied measurements by Rubin and others, and proposed that physicists hadn’t been missing matter; instead, they’d been wrongly assuming that they completely understood how gravity works. Since the outer stars and gas clouds orbit galaxies much faster than expected, it makes more sense to try to correct the standard view of gravity than to conjure an entirely new kind of matter.

Milgrom proposed that Isaac Newton’s second law of motion (describing how the gravitational force acting on an object varies with its acceleration and mass) changes ever so slightly, depending on the object’s acceleration. Planets such as Neptune or Uranus orbiting our sun, or stars orbiting close to the centre of our galaxy, don’t feel the difference. But far in the outlying areas of the Milky Way, stars would feel a smaller gravitational force than previously thought from the bulk of matter in the galaxy; adjusting Newton’s law could provide an explanation for the speeds Rubin measured, without needing to invoke dark matter.

Developing the paradigm of a dark-matter-less universe became Milgrom’s life project. At first, he worked mostly in isolation on his proto-theory, which he called Modified Newtonian Dynamics (MOND). ‘For more than a few years, I was the only one,’ he says. But slowly other scientists circled round.

He and a handful of others first focused on rotating galaxies, where MOND accurately describes what Rubin observed at least as well as dark matter theories do. Milgrom and colleagues then expanded the scope of their research, predicting a relationship between how fast the outside of a galaxy rotates and the galaxy’s total mass, minus any dark matter. The astronomers R Brent Tully and J Richard Fisher measured and confirmed just such a trend, which many dark matter models have struggled to explain.

When space-time gets curved in a particular way it creates the illusion of dark matter

Despite these successes, Milgrom’s modification of Newton’s second law remained just an approximation, causing his ideas to fall short of requirements for a full-fledged theory. That began to change when Milgrom’s colleague Jacob Bekenstein at the Hebrew University of Jerusalem extended MOND to show it could be consistent with Albert Einstein’s theory of general relativity, which predicts that gravity has the power to bend light rays, an idea proven just over a century ago, during a solar eclipse in 1919, and today known as ‘gravitational lensing’.

Around the same time, the American astronomer Edwin Hubble noticed that his colleagues had considered that close groups of gas clouds were actually far more distant galaxies. Building on Hubble’s discovery, other astronomers demonstrated the existence of larger cosmic structures now known as galaxy clusters, which have the power to act like powerful lenses, strongly bending light rays. Using formulas based on predictions by Einstein, it’s possible to infer the mass of a cosmic lens. Based on this mathematics, many physicists used gravitational lensing as an argument for the existence of dark matter. But Bekenstein showed that general relativity and MOND could also explain at least some lensing measurements that have been made.

Even so, these ideas were only partly formed. Indeed, Milgrom and Bekenstein still didn’t know what in physics could create a modified law of gravity.

MOND lacked much of a foundation until a few years ago, when the Dutch physicist Erik Verlinde began developing a theory known as ‘emergent gravity’ to explain why gravity was altered. In Verlinde’s view, gravity, including MOND, emerges as a kind of thermodynamic effect, related to increasing entropy or disorder. His ideas build on quantum physics as well, viewing space-time and the matter within it as originating from an interconnected array of quantum bits. When space-time gets curved, it produces gravity, and if it’s curved in a particular way, it creates the illusion of dark matter.

Verlinde’s research is still waiting to be fleshed out. It’s still not clear, for instance, how modified or emergent gravity can make sense of the structure of the young Universe, discerned from relic radiation left behind from the Big Bang. Astrophysicists have used space telescopes to map out that radiation in incredible detail, but they haven’t yet found a way to make models without dark matter consistent with the measurements. ‘It’s not like this idea of emergent gravity can compete yet,’ Verlinde says, but in time it could become a real alternative to dark matter.

Dark matter theories make predictions too: if this form of matter exists, numerous subatomic dark matter particles should be frequently whizzing through our solar system, through the Earth, and even occasionally zipping through our bodies. But if huge amounts of dark matter indeed exist, enshrouding every galaxy in the Universe while being unseen and unfelt everywhere, then the elusive little particles typically won’t interact with normal matter in a way that anyone would notice. That makes actually detecting them a formidable task.

While astrophysicists kept their eyes trained on the heavens, particle physicists sought to shed light on dark matter by creating plausible particles in their accelerators, like the powerful Large Hadron Collider (LHC) in Geneva, Switzerland. Intended to recreate such conditions as at the Big Bang, the LHC smashes particles together at great speeds so that, in bursts of energy, it produces new particles. Those particles pass through a series of detectors, which allow physicists to identify them.

With the LHC and its predecessors, for example, at Fermilab west of Chicago, scientists managed to find all 17 particles predicted by the ‘standard model’ of particle physics, which includes all of the fundamental forces other than gravity. (They spotted the last standard particle, the Higgs boson, with the LHC in 2012.) Because of this string of successes, physicists were bullish about soon discovering dark matter particles as well, writes Dan Hooper, a Fermilab physicist, in his book At the Edge of Time (2019).

Interest in dark matter spawned a new generation of experiments, which Hooper and his colleagues hoped would finally pin down the mysterious particles. Scientists around the world built detectors deep beneath the Earth, often repurposing old mines, with the aim of finding dark matter particles while avoiding the cacophonous noise of cosmic rays and solar particles that would bombard any detector above ground. Dark matter particles could silently flit through a detector made of xenon or other materials and leave a sign of their passing in the form of heat, the researchers hypothesised. If the experiments fared as planned, scientists would finally spot dark matter particles and herald a new era of cosmology and particle physics.

If dark matter particles exist, it will be extremely difficult to catch any glimpse of them

But the experiments haven’t turned up any positive signs, and researchers’ initial hopes have been dashed. In fact, experiments unable to find a hint of dark matter have ultimately shown evidence only of what dark matter is not. With each new experiment, the range of not-dark-matter has grown. Physicists have begun to understand that, if dark matter particles exist, it will be extremely difficult to catch any glimpse of them.

In particular, the situation looks bleak for WIMPs, which had been the most popular dark matter candidate. Researchers kept broadening their search, seeking ever-lower mass particles, and then even smaller particles, but continued to find nothing. A few teams continue the hunt for WIMPs with ever-more sensitive detectors, but in a few years they’ll reach the tiniest mass range, when any putative dark matter particle would interact with a detector similarly to how wispy neutrinos from the Sun do, effectively bringing the WIMP search to a screeching halt. ‘Then we will be done. You can see the end is in sight for the WIMPs. That may make people try to think of new things,’ says Peter Graham, a theoretical physicist at Stanford University in California.

But if the end is nigh for WIMPs, it’s certainly not the end of the story for dark matter searches, Graham argues. Scientists are already beginning to flock to other viable particles, especially axions. If they exist, axions would be billions of times less massive than WIMPs, and so they’d have to be incredibly abundant to add up to the expected mass of dark matter. Other, arguably more exotic candidates include so-called ‘sterile neutrinos’ and tiny primordial black holes, a version of MACHOs (for ‘massive compact halo objects’).

A few scientists, including Hooper, have even proposed hypothetical particles that experience hidden forces. These dark particles, if they exist, would annihilate and then decay into other particles that might somehow be coupled to known particles such as the Higgs boson. It’s plausible, but no one has made a clear detection of any of these hidden particles or forces yet.

As searches for dark particles falter, Milgrom has seen more physicists open to modified gravity in recent years. ‘People are not quite disillusioned, but there is a lot of disappointment with the fact that dark matter has not been detected,’ he said. ‘To me, that’s not the best reason to work on MOND, but I’m glad to see more interest.’ Whether this interest eventually translates into expanding research on modified gravity remains to be seen.

Hundreds if not thousands of astrophysicists, astronomers and particle physicists now study every aspect of dark matter and every imprint it might have on the cosmos, with state-of-the-art computers, telescopes and particle accelerators. Dark matter research has dwarfed modified gravity research for decades, but it doesn’t necessarily mean that dark matter is that much more convincing a theory. Instead, early on, some scientists thought it was a natural solution, others followed their view, and the scales tilted to their side.

Today’s seeming dominance of dark matter wasn’t inevitable. The processes through which scientists develop theories are heavily influenced by all sorts of historical and sociological factors, a point eloquently made by Andrew Pickering, emeritus philosopher of science at the University of Exeter and the author of Constructing Quarks (1984), a 36-year-old book that’s still relevant today.

It’s important to pay attention to who decides which phenomena to study, which research earns major government grants, which big experiments get funded, who gets speaking opportunities at scientific conferences, who is media savvy, who wins prominent fellowships and awards, and who gets promoted to high-profile faculty positions. Different choices sometimes can shape the future trajectory of science. And when choices by theorists and experimentalists coincide symbiotically, Pickering argues, it can be challenging for an upstart theory – such as modified gravity – to get a fair hearing.

The enterprise of science isn’t a particularly efficient or straightforward path toward ‘the truth’. Nevertheless, we need not despair, argues Naomi Oreskes, a historian of science at Harvard University in Massachusetts and the author of the book Why Trust Science? (2019). Though individual scientists are fallible and have their own values and goals and, occasionally, axes to grind, science as a collective affair goes on. Researchers might make missteps here and there, they might take a long time to rigorously vet some claims and establish others, and maybe a seemingly promising research programme reaches a dead end, but over time, scientists gradually build a consensus. It usually takes a while, but they eventually figure out which research paths should be left behind, and which ideas need to be studied further and refined.

For dark matter versus modified gravity, this process hasn’t finished playing out. Dark matter is currently ascendant but the debate’s not over. The stakes are large, since the future of cosmology depends on the choices that astrophysicists make next.

Modified gravity scientists such as Milgrom and Verlinde face daunting challenges before having a real chance of developing their ideas into a valid alternative to dark matter. The biggest obstacle comes from the beginning of the Universe.

The astronomers Arno Penzias and Robert Wilson in the 1960s at first misinterpreted their radio telescope’s faint static as noise – perhaps due to pigeons roosting and leaving droppings on it. But the signal turned out to be real, and they confirmed their discovery of relic radio waves that date back to soon after the Big Bang. Then in the 1980s and ’90s, Soviet and NASA scientists used their own space telescopes, RELIKT-1 and COBE, to spot tiny wiggles in that radiation. John Mather and George Smoot, the physicists who led the COBE research, won the Nobel Prize in Physics 2006 for measuring those little radiation variations, which translate into early density differences that determined where the matter in the Universe collected and structures of galaxies formed.

They predict far more dark matter clumps than suggested by the meagre number of satellite galaxies spotted so far

Mather and Smoot’s successors have now measured the wiggles in relic radio radiation to exquisite precision, and any successful theory has to offer an explanation of them. Dark matter physicists have already shown that their theory could reproduce all of those wiggles quite well, but modified or emergent gravity has failed that critical test – so far. Bekenstein died in 2015, but his successors are still trying to make his modified gravity theory consistent with at least some of the measurements. That would be a big leap forward and a compelling one for skeptics of modified gravity, but it’s a major task that has yet to be done.

Of all the pieces of evidence, those wiggles are the strongest. Dark matter is clearly winning. It took decades of work by hundreds of dark matter scientists and huge investment in their research programmes to develop models that could explain all those measurements. Modified and emergent gravity, with lower levels of funding, remain far behind, but that doesn’t mean they should be abandoned. ‘My contention is that it’s very unlikely that emergent gravity is responsible for the phenomena we currently attribute to dark matter,’ Hooper says, ‘but it doesn’t mean that gravity isn’t emergent or that it’s not something worth exploring.’

Furthermore, dark matter researchers such as White and Hooper have their own problems to grapple with. Giant galaxies, including our own, typically have a handful of smaller galactic companions orbiting them like satellites. If dark matter physicists are right, each of those galaxies should be embedded within a huge clump of dark matter since dark matter particles and the galaxies’ stars should be drawn together by the same gravitational forces. But the latest computer simulations developed by White and his colleagues have some glaring differences with astronomers’ observations: they predict far more dark matter clumps than suggested by the meagre number of satellite galaxies spotted so far. Physicists tellingly call this the ‘missing satellites problem’, since reality doesn’t seem to match those theorists’ expectations.

At much larger, cosmic scales, astrophysicists are also trying to explain a recent, puzzling discrepancy: that the Universe today seems to be expanding dramatically more rapidly than it did in its infancy. Physicists had expected the rate of expansion (called the Hubble constant) to be the same everywhere, but now they need to explain the disparity. With dark matter theorists unable to resolve the conundrum, Verlinde says perhaps emergent gravity will offer a path ahead.

Verlinde, Milgrom and their colleagues are still a small minority, but cosmology will benefit if their ranks grow. They’re already finding a few scientists in the dark matter community to be receptive to their ideas. At a recent conference he attended, Verlinde noticed a palpable shift in acceptance. ‘I felt like there was more communication and more willingness to discuss alternatives than years before,’ he says.

Beyond this theoretical work, physicists expect bigger, better telescopes and experiments to bear fruit, including the Large Synoptic Survey Telescope, being built in the dry mountains of northern Chile. This year, scientists renamed it the Vera C Rubin Observatory, and it will have ‘first light’ next year. Inspired by Rubin’s work, researchers will peer wider and deeper into the heavens, mapping the light of billions of galaxies. If they keep an open mind, their studies could illuminate both dark matter and dark forces of gravity. Rubin’s namesake will continue provoking healthy debates about the vast hidden universe we yearn to further explore.

This Essay was made possible through the support of a grant to Aeon from the John Templeton Foundation. The opinions expressed in this publication are those of the author and do not necessarily reflect the views of the Foundation. Funders to Aeon are not involved in editorial decision-making.
This is the paper by Rubin that started this nonsense.

ROTATION OF THE ANDROMEDA NEBULA FROM A SPECTROSCOPIC SURVEY OF EMISSION REGIONS
http://articles.adsabs.harvard.edu/pdf/ ... .159..379R

These are most of the links that the article referenced. Those links that went to a paywall I found alternate links instead. This was quite a harvest to show what happens when you ignore electricity when looking at the universe. You get twisted into "nots". HA!

Core condensation in heavy halos: a two-stage theory for galaxy formation and clustering.
https://ui.adsabs.harvard.edu/abs/1978M ... W/abstract

Deep science at the frontier of physics
https://sanfordlab.org

IceCube
https://icecube.wisc.edu/about/overview

A modification of the Newtonian dynamics as a possible alternative to the hidden mass hypothesis
https://ui.adsabs.harvard.edu/abs/1983A ... M/abstract

Reprint of 1977A&A....54..661T. A new method of determining distance to galaxies
https://ui.adsabs.harvard.edu/abs/1977A ... T/abstract

Relativistic gravitation theory for the MOND paradigm
https://arxiv.org/abs/astro-ph/0403694

Curving the Universe
https://aeon.co/essays/einstein-v-newto ... al-eclipse

Emergent Gravity and the Dark Universe
https://arxiv.org/abs/1611.02269

A Measurement of Excess Antenna Temperature at 4080 Mc/s
https://ui.adsabs.harvard.edu/abs/1965A ... P/abstract

The Real Problem with MOND
https://arxiv.org/abs/1112.1320

Where are the missing galactic satellites?
https://arxiv.org/abs/astro-ph/9901240

Steel man

by allynh » Fri May 22, 2020 9:11 pm

Oh, this is such a fun concept, I've never heard the phrase before.

I've heard of "straw man", and seen a ton of people basically lie and distort what the other person was saying, but I'd never heard the counter phrase, "steel man".

Steel man

From Lesswrongwiki
https://wiki.lesswrong.com/wiki/Steel_man
Sometimes the term "steel man" is used to refer to a position's or argument's improved form. A straw man is a misrepresentation of someone's position or argument that is easy to defeat: a "steel man" is an improvement of someone's position or argument that is harder to defeat than their originally stated position or argument.
I've done that for decades without realizing that there was a term for it.

I will take a concept that makes no sense and show how to make it better. I have no fear of embracing something, trying to understand what is being said, and then deciding if it makes sense, even if I have to go so far as to rephrase things to have it make sense.

I won't give examples because they are outside the limits of this Forum, but I would like to see people actually try to get inside somebody else's argument and make it better rather than just blatantly "straw man" somebody.

When I was a kid in Silver City, about third grade, I came across a high school debate club. I have never seen anything similar since.

The debate club would have everybody learn a subject, completely. Then they would break into two teams, and the audience. They would then flip a coin at the last minute to decide who was "pro" and who was "con".

- The two teams would face off and debate, with the audience scoring how well each side did.

- Each side had to honestly embrace their side of the debate.

If you had one team taking a side that they did not like, and proceeding to trash their side with "straw man" arguments, they would be scored down.

The debate was about making sure everyone knew the subject being debated. There was none of the nonsense of using the debate to "inform" the audience, since the audience was scoring the debate they had to know everything as well as the debaters.

I have never seen a debate like that since. Most so called "debates" are simply "arguments" in front of an audience that was not informed.

- An "argument" is when one or both sides is ignorant of the facts.

Whenever I see someone want to "debate" someone, they really want to "argue".

Watch any of the so called "debates" by Intelligence Squared on YouTube and you will see how it is rigged by how the audience votes. They have the audience vote at the beginning and at the end. Whichever side has the greatest change in the vote "wins".

What the audience will do is vote counter to their real position at the start, then vote what they really believed, thus their side "wins". The audience thus "rigs" the debate.

IntelligenceSquared Debates
https://www.youtube.com/user/IntelligenceSquared/videos

Don't get me wrong, I love watching Intelligence Squared, the way John Donvan runs the whole thing -- he's got style -- but they are not debates.

How the sun shines

by allynh » Wed May 13, 2020 5:33 am

This is one of those posts that no one will read the links or understand what I'm pointing out. If people read all of the links they will see the evolution of the "narrative" of how the Sun works. Notice as you read along, that the current dogma was arrived at by editorial fiat, not by actual science.

Basically, after reading through the old physics texts, watching them build their narratives with what they thought was valid science, I am not comfortable with the current dogma of consensus science.

- I have not seen any proof that "neutrinos" even exist

- I have not seen any proof that "fusion" occurs

Those have been the most shocking insights that I've had while reading this stuff.

BTW, I'm not interested in arguing or reading anything "theoretical", I've read enough of that. One hundred years of "claiming" that "neutrinos" and "fusion" is real -- with no physical proof -- is enough for me.

- If anybody has links to papers actually showing "physical proof" of "neutrinos" or "fusion" I will be glad to read them.

Here are the links:

First off, look at this cartoon, and understand the implications.

Answers
https://i.imgur.com/ZiTPzYl.png

If you can't acknowledge what the cartoon is saying, then don't bother reading the links. HA!

This is Lord Kelvin talking about the Sun being powered by compression due to gravity. They did not know about radioactivity.

On the Age of the Sun’s Heat
https://zapatopi.net/kelvin/papers/on_t ... _heat.html

- Read the article, and follow his "logic" and compare it to any modern description of the Sun.

Compare that to now, when they assume that "fusion" powers the Sun. Yet no one has ever proven that "fusion" is valid. No one has ever taken hydrogen and made helium, despite all the claims.

This is Bohr's Nobel Prize lecture from 1922 about the atom. They first published the model in 1913.

The structure of the atom
https://www.nobelprize.org/uploads/2018 ... ecture.pdf

This is Eddington's 1920 essay:

- Notice, he thought stars started as red giants, then over time compressed into dwarf stars. Now the dogma says that red giants are the oldest.

- The key point to notice, is that they are still working under the assumption that Lord Kelvin pushed on them, that the stars were powered by gravity compression.

- Also, Eddington keeps pushing "ethereal heat" as part of the process.

- Only at the end of the paper does he mention "sub-atomic energy" and "transmutation" rather than Lord Kelvin's theory. He leaves it up to the reader to decide if the source is better than gravity compression, still trying not to upset people who follow Lord Kelvin.

- He mentions about the discrepancy of four hydrogen atoms being heavier than one helium atoms, and that no other atom has that occur.

The Internal Constitution of the Stars
http://articles.adsabs.harvard.edu/cgi- ... etype=.pdf

This is Eddington's 1926 book:

The Internal Constitution of the Stars
by A.S.Eddington
https://archive.org/details/TheInternal ... s/mode/2up

- In just six years they felt that "sub-atomic energy" answered the question, yet still used gravity compression as part of the process to generate energy.

- Read Chapter 1 and be amazed at how speculative everything is.

- He also talks about "aether waves", meaning "light".

The first sentence of Chapter II is:

"Radiant energy or radiation consists of electromagnetic waves in the aether."

This was 1926, and if you didn't take aether seriously, and mention it in your work, you were not doing "science".

BTW, In reading Einstein's War, Einstein started with the "ether" as well. As far as everybody was concerned "ether" was established science.

Now read the original paper by Hans Bethe. Compare what he is saying to Lord Kelvin, and tell me that either makes sense.

Energy Production in Stars

H. A. Bethe
Phys. Rev. 55, 434 – Published 1 March 1939
https://journals.aps.org/pr/abstract/10 ... Rev.55.434

- They took the concept that four hydrogen atoms weigh more than one helium atom, and spun the fantasy of "fusion" powering the Sun from there, with imaginary "neutrinos" making up the balance.

- What's worse, is that larger stars go through the "CNO cycle" to generate helium. Complexity on complexity.

- Notice: Even in 1938 Bethe was having to discuss gravity compression as a power source. Lord Kelvin had a massive impact all this time later.

- He also had to refer to Eddington's work or he would be ignored.

Those are the original texts, these are articles discussing the historical texts.

The Age of the Sun: Kelvin vs. Darwin
http://rhig.physics.wayne.edu/~sean/sea ... insunf.pdf

- This is Lord Kelvin talking about the Sun being powered by compression due to gravity.

The Source of Solar Energy, ca. 1840-1910:
From Meteoric Hypothesis to Radioactive Speculations
https://arxiv.org/pdf/1609.02834.pdf

This is a deeply disturbing article showing how the politics of science forced how the concepts were presented. It was only after the fact that she was declared "right".

EXTRAORDINARY CLAIMS REQUIRE EXTRAORDINARY EVIDENCE
http://articles.adsabs.harvard.edu/cgi- ... etype=.pdf

All the above leads to the current dogma in this article from the Nobel Prize people.

How the sun shines
https://www.nobelprize.org/prizes/theme ... n-shines-2

When you read through everything you can see how the "narrative" was developed, with no actual science.

BTW, I'm still trying to finish reading Einstein's War where Eddington, along with others of the day, made Einstein into a rock star.

How Fundamental Physics Lost Its Way

by allynh » Tue Mar 17, 2020 7:11 pm

I'm halfway through reading Einstein's War, it's deeply disturbing so far, and now I read this book review on the NYTimes for, The Dream Universe.

Has Physics Lost Its Way?
https://www.nytimes.com/2020/03/17/book ... ndley.html
By Jim Al-Khalili
March 17, 2020, 5:00 a.m. ET
Nonfiction
Joanna Neborsky

THE DREAM UNIVERSE
How Fundamental Physics Lost Its Way
By David Lindley

The title of David Lindley’s new book, “The Dream Universe,” may be unprepossessing, but his subtitle — “How Fundamental Physics Lost Its Way” — tells you what to expect: a polemical argument from a writer who won’t be pulling his punches.

I was keen to discover whether Lindley, an astrophysicist and the author of several well-regarded books, including “Uncertainty” and “The Science of Jurassic Park,” follows a line of reasoning that we’re beginning to see more frequently in popular science writing today: another full-throated critique of the more exotic speculations in theoretical physics like superstring theory, parallel universes, the properties of black hole event horizons and the hidden dimensions of space and time. Progress in our understanding of these phenomena seems lately to have stalled. Maybe Lindley, I thought, would offer some guidance as to how “fundamental physics” could find its way back to the right path.

Wider discussions about the nature of science and how it works are vitally important in our world of shouty social media, conspiracy theories, fake news, confirmation bias and cognitive dissonance. We need to trust the scientific method when it comes to issues like climate change or vaccines. But the multiverse theory? Is that even proper science?

Lindley begins with the Greek philosophers, notably Plato, who he says was not interested in the physical world, only in theorizing about it from on high, contemplating its mathematical (geometrical) beauty. Even worse, he looked with disdain at observational science. By contrast, his student Aristotle, interested in examining the world around him and trying to explain it, is a better fit as a precursor to the modern-day scientist. But Aristotle too came unstuck, for, as Lindley explains, he would come up with a hypothesis about some aspect of nature, then sift through his data to cherry-pick those that agreed with it — committing what we would now call confirmation bias, which, by the way, is how a lot of pseudoscience and conspiracy theories on the internet work.

Of course, Lindley reminds us, what constitutes a good scientific theory depends on the scientific context of its time. Surely not, you might think; don’t proper scientific theories have to satisfy timeless criteria such as explaining all the phenomena the theories they displace are able to, being able to make testable predictions, being repeatable, and so on? Well, yes, but here is where we get to Lindley’s central thesis: Contemporary theoretical physicists seem to have reverted to the idealized philosophy of Platonism. As he puts it, “The spirit of Plato is abroad in the world again.” Is this true? Plato’s stance was that it was enough to think about the universe. Surely, we can do better than that today, with our far more powerful mathematical tools and an abundance of empirical data to test our theories against. No physicist I know would say that to understand the laws of nature it is sufficient to think about them.

While it’s clear that nature obeys mathematical rules, a happy middle ground between Plato and Aristotle would seem to be preferable: to make the math our servant, not our master. After all, mathematics alone cannot entirely explain reality. Without a narrative to superimpose on the math, the equations and formulas lack a connection with physical reality. Lindley makes this point forcefully: “I find it essentially impossible to think of physical theories and laws only in mathematical terms. I need the help of a physical picture to make sense of the math.” About this, I am in total agreement. The mathematics can be as pretty and aesthetically pleasing as you like, but without a physical correlative, then that is all it is: pretty math.

According to Lindley, something happened in 20th-century theoretical physics that caused some in the field to “reach back to the ancient justifications for mathematical elegance as a criterion for knowledge, even truth.” In 1963, the great English quantum physicist Paul Dirac famously wrote, “It is more important to have beauty in one’s equations than to have them fit an experiment.” To be fair, Dirac was a rather special individual, since many of his mathematical predictions turned out to be correct, such as the existence of antimatter, which was discovered a few years after his equation predicted it. But other physicists took this view to an extreme. The Hungarian Hermann Weyl went as far as to say, “My work always tried to unite the truth with the beautiful, and when I had to choose one or the other, I usually chose the beautiful.” Lindley argues that this attitude is prevalent among many researchers working at the forefront of fundamental physics today and asks whether these physicists are even still doing science if their theories do not make testable predictions. After all, if we can never confirm the existence of parallel universes, then isn’t it just metaphysics, however aesthetically pleasing it might be?

But Lindley goes further by declaring that much fundamental research, whether in particle physics, cosmology or the quest to unify gravity with quantum mechanics, is based purely on mathematics and should not be regarded as science at all, but, rather, philosophy. And this is where I think he goes too far. Physics has always been an empirical science; just because we don’t know how to test our latest fanciful ideas today does not mean we never will.

Lindley is engaging and very nearly persuasive. He believes we should continue to ask deep questions about reality but concludes that science will be unable to answer them. I am not nearly as pessimistic. Maybe we just need to try harder.
Go to Amazon and download the book sample. Read it, then compare the sample to the book review, and you will see that the person doing the book review is confusing "Theoretical Physics" with actual science, and is acting as an apologist for "Theoretical Physics" rather than looking at reality.

I forget who said it, but they said clearly:

- "Physics" is not theoretical.

Over the past century science and technology has leapt forward in astonishing ways, yet "Theoretical Physics" has simply gotten bizarre. I went to University in the 1970s and "Theoretical Physics" made no sense even then. Over the decades since it has made less and less sense.

I'm definitely buying this book.

The Case Against Reality

by allynh » Wed Feb 26, 2020 7:32 pm

I can see what Mel Acheson is trying to do in his TPOD, but things are actually stranger than what he's talking about.

Really?
https://www.thunderbolts.info/wp/2020/02/26/really/

Donald Hoffman has a book out, The Case Against Reality, that shows we are not evolved to see reality. So when people talk about "seeing the real world" sorry that doesn't happen.

Essentially:

- consciousness is fundamental and physical reality is not fundamental

I first stumbled across Hoffman's work with his book review and TED talk. It's been falling down the rabbit hole ever since as I watched all of the videos and read his stuff.

Review of the book:

The case against reality
https://www.socsci.uci.edu/newsevents/n ... eality.php
The scientific method has been spectacular in terms of helping us to see where we’re wrong. And that’s the key. That’s my attitude about science. Be precise so we can find precisely where we’re wrong. We need to learn what ideas are useful and which are wrong so we can evolve on all fronts.
Start with his TED talk. Notice at the end the head of TED is deeply upset by the talk.

Do we see reality as it is? | Donald Hoffman
https://www.youtube.com/watch?v=oYp5XuGYqqY

A clip from Through the Wormhole:

Can We Handle The Truth?
https://www.sciencechannel.com/tv-shows ... -the-truth

This is his website:

Donald D. Hoffman
http://www.socsci.uci.edu/~ddhoff/

Read this paper once you have watched all of the videos:

Conscious Realism and the Mind-Body Problem
http://www.cogsci.uci.edu/~ddhoff/ConsciousRealism2.pdf

Watch all of the videos first, it really does help understand the book.

Closer to the Truth series:
The host, Robert Lawrence Kuhn, is having real trouble with what Hoffman is saying, that consciousness is fundamental and physical reality is not fundamental.

Donald Hoffman - Does Consciousness Cause the Cosmos?
https://www.youtube.com/watch?v=Jv25EcaUQBo

Donald Hoffman - Can Religion Survive Science?
https://www.youtube.com/watch?v=NbyRrFUncAw

Donald Hoffman - Does Human Consciousness Have Special Purpose?
https://www.youtube.com/watch?v=m_zaMO3vdDA

Donald Hoffman - Does Evolutionary Psychology Explain Mind?
https://www.youtube.com/watch?v=KIGcRLAYSoM

Donald Hoffman - Computational Theory of Mind
https://www.youtube.com/watch?v=cUhrK82seVY
Science and Nonduality lectures:
Reality is a User Interface: Donald Hoffman
https://www.youtube.com/watch?v=lSrzlkfA0jk

The Mystery of Free Will: Donald Hoffman
https://www.youtube.com/watch?v=cT7hf8NOEk4

The Death of SpaceTime & Birth of Conscious Agents, Donald Hoffman
https://www.youtube.com/watch?v=oadgHhdgRkI

Entangling Conscious Agents, Donald Hoffman
https://www.youtube.com/watch?v=6eWG7x_6Y5U

Conscious Agents A Theory of Consciousness, Donald Hoffman
https://www.youtube.com/watch?v=7E-MwJgy2lI

Consciousness and The Interface Theory of Perception, Donald Hoffman
https://www.youtube.com/watch?v=dqDP34a-epI

Notice, Chopra has problems dealing with the conversation. It's almost too far out even for him.

Deepak Chopra and Donald Hoffman: Reality is Eye Candy
https://www.youtube.com/watch?v=IxWkwy8z-Jg
I'll end this post with one of my favorite quotes:

The border between the Real and the Unreal is not fixed, but just marks the last place where rival gangs of shamans fought each other to a standstill.

-- Robert Anton Wilson

Paradox Lost

by allynh » Mon Feb 24, 2020 10:19 pm

Watch this video.

Relativity: how people get time dilation wrong
https://www.youtube.com/watch?v=svwWKi9sSAA

It's part of a series of beautiful videos from Fermilab, that are absolutely wrong. You need to watch them, and you will see the problem. He keeps pointing out that things don't make sense, that they create a "Paradox".

That's the point.

- If you have a "Paradox" then you are not looking at all of the information.

- If their is a "Paradox" it is wrong, and you have to find what is wrong in your experiment.

- If after all of your experiments, and the "Paradox" is still there, then you are missing something, or adding something that is not there.

Does this guy actually believe what he is saying? Possibly, but "belief" is not science.

Don't get me wrong, a "Paradox" is a great starting point for experimentation, so they are very useful things.

Example:

Look at Olbers' Paradox, asking why is the night sky dark instead of being filled with light. There is no "Paradox" because if you look at the night sky, with the right equipment, you will see light everywhere. They had a "Paradox" in the past, because they did not have enough information, or the right equipment.

There is nothing wrong with Olbers' Paradox as a great starting point for experiment to find out if there are any dark regions of the sky, but it is just a starting point.

Now, let's get to the "Twins Paradox" and "time dilation".

I can't remember which EU lecture I watched, but one guy who worked at CERN pointed out that when grad students show up for work, the first thing the professor has to tell them, is:

- Time dilation does not occur.

CERN accelerates particles close to the speed of light, and time does not "dilate" for those particles. The energy built up in the particles become other particles when they collide, but I digress.

- Too many people are invested in "Twins Paradox" and "time dilation" to let it go.

The example that people always give is of high energy mesons living longer than low energy mesons as being evidence of "time dilation", and that contains the actual answer. High energy particles simply have a different "lifespan" than low energy particles. It does not mean that time "dilates". That is a leap too far.

- "Time dilation" is a fun concept that is used in fiction, like elves and dragons, but does not exist in reality. ex., Tau Zero by Poul Anderson is great science fantasy.

So no matter how fun the "thought experiment" seems, "time dilation" is still simply imagination, not reality, until it is shown to occur by experiment.

Now, hold on, you say, "time dilation" has been proven by experiment, time and again. (See what I did there. HA!)

Actually, no it has not.

PBS NOVA had a great program about atomic clocks and "time dilation":

Inside Einstein's Mind.
https://www.pbs.org/wgbh/nova/video/ins ... eins-mind/

Look at the transcript on the page. Here is the main part:
NARRATOR: Today, 100 years after general relativity was first presented, new technology is allowing us to explore the most remarkable predictions of the theory: an expanding universe; black holes; ripples in space-time; and perhaps the most bizarre, the idea that not just space, but time, itself, is distorted by heavy objects.

NARRATOR: To prove it, a team of physicists is carrying out a remarkable experiment. They're using two atomic clocks that are in near perfect sync, accurate to a billionth of a second. The master clock remains at sea level while they take the second clock to the top of New Hampshire's Mount Sunapee.

General relativity tells us that as you move away from the mass of the planet, time should speed up. After four days at the top of the mountain, the test clock is taken back to the lab for comparison. There, they compare it to the sea level master clock. Four days ago they were in ticking in unison. But what about now?

DAVID SCHERER (Microsemi Corporation): You guys ready? This is it, right here. The time interval counter is going to show us the time difference between these two clock ticks.

Twenty nanoseconds!

You can see the time difference between them represented here, graphically: the clock that was up at the mountain for four days and our master clock.

NARRATOR: Gravity, the distortion of space and time, becomes weaker as you move away from the surface of the planet, so while the test clock was up the mountain, time sped up. It's now 20 nanoseconds, 20 billionths of a second, ahead of the sea level clock.

DAVID SCHERER: This is awesome.

NARRATOR: This distortion of time has surprising consequences. The Global Positioning System, something we all take for granted, wouldn't work without taking this into account. The engineers who built the G.P.S. system we use every day to pinpoint locations, had to ensure it adjusted for the time difference between clocks on satellites and receivers on the ground. If they didn't, G.P.S. would be off by six miles every day.

JIM GATES (University of Maryland): Your G.P.S. units use the results of general relativity. When you navigate in your car, you perhaps should give a word of thanks to Uncle Albert.
They had two atomic clocks sitting side-by-side in the lab. They synchronized the atomic clocks. They then took one atomic clock to the top of a mountain, left it there a few days, then brought it back down and compared the time shown on each atomic clock, and they did not match! The moved atomic clock was running faster than the stationary atomic clock.

- This shows that time moves slower based on gravity.

No, sorry, it does not.

The atomic clock that was taken to the top of the mountain was shaken by the journey. To test that, they should have one atomic clock on a shake table, shake it a while, then compare the time shown. That would be an experiment.

The other experiment they did was have an atomic clock in the lab and compare that to atomic clocks in the GPS satellites in Earth orbit(12,247 miles). Over time, the measured time starts to diverge, with the GPS atomic clocks running "faster" than the lab.

- This shows that time moves slower based on gravity.

Wow, that is so wrong.

The GPS atomic clock is moving at high speed, that means it should slow down, not get faster. Remember that stunt, decades ago, of flying atomic clocks in jet planes to show that they would slow down, and they did! Really? no, they didn't, they just got shaken, a lot!.

Yes, they took the speed of the GPS satellites into account, slowing down the clocks, and the height of the GPS satellite, and "declared" their results.

The real experiment would be to have an atomic clock sitting in geostationary orbit(22,236 miles) above the Earth, another atomic clock in a lab on the Earth, and compare those to the GPS satellites.

Guess what, the atomic clock in geostationary orbit is moving way faster than the GPS satellites, and is actually far enough away from the Earth to be in an even lower gravity than the GPS satellites, with the inverse-square law reduction.

- Earth radius, 3,950 miles

- GPS satellites, 12,247 miles

- geostationary orbit, 22,236 miles

Now that would be an experiment. The trouble is, they keep resetting the atomic clocks to synchronize them.

- That constant tweaking of the atomic clocks invalidates the experiment.

- No matter how well each atomic clock matches the other, they are not the same, will not work the same, will "drift" no matter what.

Every step along the way error is introduced into the system. Measuring the atomic clocks, transmitting the data, etc... So many errors built into the experiment itself. The "result" that they come up with floats within that "error". That makes it noise. They need to develop an experiment that gives results outside that "error" before they can claim a "result".

I was at University in the 1970s, getting my BS in Civil Engineering. (Yes, go ahead and play with the "BS" part. I'll wait. HA!)

In Chemistry, they had us do a deeply disturbing experiment that apparently these guys forgot, and is part of what is wrong with all the experiments mentioned.

We had electronic scales to measure weights at incredible accuracy for the day. They sat in their own little enclosures because a puff of air could change the results.

We took brass weights, a test weight. The scales were so accurate that we could not touch the weight with our fingers because it would weigh our fingerprints. We measured each test weight on two different electronic scales, and saw with precision that each scale measured a different value for each weight.

Think of it.

- Identical instruments, giving different values for the same test weight.

Even day to day, using only one electronic scale, the values will change over time because the instrument "drifts".

- When they report experiments on science programs, or you read the papers, if they do not report the "error" within the experiment, then they are not reporting science.

Remember, you can use "Paradox" to inspire experiments, that's awesome. But if all you have is "Paradox" then you do not have an answer.

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