Lambda-CDM - EU/PC Theory - Confirmation Bias

Plasma and electricity in space. Failure of gravity-only cosmology. Exposing the myths of dark matter, dark energy, black holes, neutron stars, and other mathematical constructs. The electric model of stars. Predictions and confirmations of the electric comet.

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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby jacmac » Mon Jan 14, 2019 11:08 am

Higgsy:
Don't be stupid. I know what a flat rotation curve is. I simply don't know what point he is trying to make about it,

My Bad.
Of course you know the flat rotation curve problem.
You are very good with all kinds of personal insults, and higher maths, and debating details of whats wrong with EU ideas, the more esoteric the better, while loosing sight of the fundamental problem at hand.
The mainstream assumption that "there is no electricity in space" is wrong.

There is ubiquitous magnetism on gigantic scales....but no electricity.
The known matter in space is 95%.....99.99% plasma....but no electricity.
"we haven't found batteries in space yet"....so no electricity.
???
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Higgsy » Mon Jan 14, 2019 11:32 am

Aardwolf wrote:However they are probably wasting their time as there is not likely to be any found in the lab when it's missing from the whole solar system.
Astrophysicists believe that our galaxy must be filled with more dark matter than ordinary matter. Now astronomers say they can find no evidence of dark matter’s gravitational influence on the planets. What gives?
https://www.technologyreview.com/s/516681/the-incredible-dark-matter-mystery-why-astronomers-say-it-is-missing-in-action/

Although as we know this stuff is magic, and possibly sentient, it's probably just playing hide and seek.
That's the trouble with reading popular articles and swallowing them whole without question. I know people here are averse to quantifying things but shall we do some sums? The article puts an upper limit on the mass of dark matter within a sphere of radius the orbit of Saturn of 1.7x 10-10 solar masses. So assuming the halo has uniform density (in fact the density at the Sun is less than the mean so this is a worst case), let's work out what the mass of the halo would be. The halo radius is approximately 53,000 light years. The radius of Saturn's orbit is 0.00015 light years. So the ratio of the two volumes is 53,0003/0.000153 = 4.4 x 1025. So the total halo weighs 4.4 x 1025 times the halo within a sphere with radius of Saturn's orbit. Multiplying the upper limit of the mass within tha sphere by that ratio gives a total mass for the halo = 4.4 x 1025 x 1.7 x 10-10 = 7.5 x 1015 solar masses. This is 1,000 times MORE than the estimated total mass of the halo which is of the order of 1012 solar masses. In other words , the sensitivity of the test is 1,000 times too low to be able to detect the dark matter by orbital perturbations in the solar system.

Another way of looking at this is that the paper claims an upper limit for dark matter density in the orbit of the Saturn of 1.1 x 10-20g cm-3. But the expected density of dark matter in the solar system is about 10-24g cm-3, ~10,000 times less. So of course the test isn't going to detect the influence of dark matter on the solar system, as it is much too little for the sensitivity of this test.

Only the authors can you tell you why they did a test and wrote a paper, when the prediction was that the test would be too insensitive by a factor 1,000 - 10,000. And you really need not to swallow popular articles on science whole.
"Every single ion is going to start cooling off instantly as far as I know…If you're mixing kinetic energy in there somehow, you'll need to explain exactly how you're defining 'temperature'" - Mozina
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Higgsy » Mon Jan 14, 2019 11:43 am

Michael Mozina wrote:Thank you Higgsy for demonstrating my point perfectly. Pure unadulterated denial is the only thing that holds your metaphysical belief system together in 2019.

Show me exactly where in the 2006 paper the mass distribution methods are flawed. Point to the exact place and explain exactly why they are flawed with references to the primary literature. You are now, and always have been incorrigible and you never learn anything from those who know better than you. I gave you a chance to learn something and to stop making a fool of yourself, but you chose to repeat the same stupidity that you've been spouting for ages.

Read my lips: Cluster collision studies do not rely on and never mention estimates of numbers of stars or galaxies in the clusters. Got it yet?
"Every single ion is going to start cooling off instantly as far as I know…If you're mixing kinetic energy in there somehow, you'll need to explain exactly how you're defining 'temperature'" - Mozina
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Higgsy » Mon Jan 14, 2019 11:46 am

jacmac wrote:The mainstream assumption that "there is no electricity in space" is wrong.

There is ubiquitous magnetism on gigantic scales....but no electricity.
The known matter in space is 95%.....99.99% plasma....but no electricity.
"we haven't found batteries in space yet"....so no electricity.
???

Who said there are no electrical currents in space? Not me and not any astrophysicist I know of. So stop with the strawman already.
Last edited by Higgsy on Mon Jan 14, 2019 11:56 am, edited 1 time in total.
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Higgsy » Mon Jan 14, 2019 11:55 am

Aardwolf wrote:
Astrophysicists believe that our galaxy must be filled with more dark matter than ordinary matter. Now astronomers say they can find no evidence of dark matter’s gravitational influence on the planets. What gives?
https://www.technologyreview.com/s/516681/the-incredible-dark-matter-mystery-why-astronomers-say-it-is-missing-in-action/

And another thing is the ridiculous popular article you link to, which is pure sensationalist rubbish like popular science articles often are. It talks nonsense like "If the Sun is surrounded by a thick soup of dark matter". Thick soup indeed, when the expected local density of dark matter is about 0.5 proton masses per cm3. The author's no more numerate than the general run of people on the forum.
"Every single ion is going to start cooling off instantly as far as I know…If you're mixing kinetic energy in there somehow, you'll need to explain exactly how you're defining 'temperature'" - Mozina
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Re: It's impossible to prove a negative.

Unread postby Michael Mozina » Mon Jan 14, 2019 11:57 am

Higgsy wrote: The matter in the spherical halo lies in a sphere whereas the stars and gas lie more on a disc, because the former is collisionless whereas the latter averages its angular momentum to zero except aroungd the vector where it had residual angular momentum in the first place. Typically the total galaxy mass within the stellar radius is 90% in the halo, 8% in stars and 2% in gas and dust. So there is no magic involved - the halo is roughly spherical and that explains the flat rotation curve in the disk without having to be exact.


That claim about the gas being located in a disk has been shown to be false *repeatedly* now. Get a grip. In fact the galaxy is surrounded by both a neutral hydrogen spherical halo, as well as a hot and "warm" plasma halo, exactly where your supposed "dark matter" resides. The halos also have more mass than all the stars combined.

https://www.nasa.gov/mission_pages/chan ... 2-331.html
https://cosmosmagazine.com/space/galaxy ... ssing-mass

Another great surprise to astronomers was the fact that the halos also rotate with the stars:

https://www.sciencedaily.com/releases/2 ... 151144.htm

And of course that movement pattern was also a big surprise to astronomers:

"This flies in the face of expectations," says Edmund Hodges-Kluck, assistant research scientist. "People just assumed that the disk of the Milky Way spins while this enormous reservoir of hot gas is stationary -- but that is wrong. This hot gas reservoir is rotating as well, just not quite as fast as the disk."


You folks haven't figured out the first thing about the mass concentrations patterns or movement patterns of the baryonic mass of our *own* galaxy, let alone any other galaxy at some great distance. Sheesh. There was no "proof" of dark matter found in that 2006 bullet clusterf*ck study, just "proof" that you folks didn't have a clue how to find the baryonic mass of a galaxy in 2006, and you still don't.
Last edited by Michael Mozina on Mon Jan 14, 2019 12:05 pm, edited 1 time in total.
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Michael Mozina » Mon Jan 14, 2019 12:03 pm

Aardwolf wrote:
Higgsy wrote:You mean, why hasn't dark matter been identified in the lab as yet? Well, the obvious answer is because it isn't one of the things that has been tested for so far.
Then what the f*** are these guys been spending money on then for the last 10 years? Is it a scam?


Yep, it's a scam alright. It's a scam to line their wallets with money so they don't give a damn about the negative results of their so called "tests". The whole concept has no useful predictive value in the lab as 10's of billions of dollars with of tests have already demonstrated repeatedly.

Higgsy can't and won't even commit himself to a single model of his metaphysical matter deity, so it's the ultimate exotic matter of the gaps claim. No matter how many "tests" they run, and no matter how many billions of dollars they waste on their useless "tests", there will always be some higher or lower energy state they didn't check, so give them more money!

In any other area of life, astronomers would be sued for false advertising and they would be put in jail.
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Michael Mozina » Mon Jan 14, 2019 1:36 pm

Higgsy wrote:
Michael Mozina wrote:Thank you Higgsy for demonstrating my point perfectly. Pure unadulterated denial is the only thing that holds your metaphysical belief system together in 2019.

Show me exactly where in the 2006 paper the mass distribution methods are flawed. Point to the exact place and explain exactly why they are flawed with references to the primary literature.


I've already done that for you throughout this entire thread, but here you go:

https://arxiv.org/abs/astro-ph/0608407

Page 3, section 3: "Stellar masses are calculated from the I-band luminosity of all galaxies equal in brightness or fainter than the component BCG. The luminosities were converted into mass assuming (Kauffmann et al. 2003) M/LI = 2."


This formula is of course *highly* suspect after more recent revelations regarding their *huge* underestimation of small stars we can't see vs. large stars, not to mention the two different plasma/gas halos that have been found since 2006 around our own galaxy and presumably every galaxy., and the fact we underestimated the light output from galaxies by a factor of two due to excess scattering that is also not included in that baryonic mass calculation.

Read my lips: Cluster collision studies do not rely on and never mention estimates of numbers of stars or galaxies in the clusters. Got it yet?


It doesn't matter if they mention the actual number of stars in a galaxy or the numbers of galaxies in a cluster. The whole stellar mass estimates were/are based on *luminosity*, and a brightness formula that has been shown to be pointless and riddled with serious flaws in later studies. First and most importantly, smaller stars don't emit enough light to contribute anything to those luminosity figures, but they make up more mass than the larger stars that do contribute to luminosity. You botched those large/small star percentages by a whopping factor of between 3 and 20 times depending on the size of the star and the type of galaxy involved. Furthermore your method basically *ignores* the neutral gas halo that was found in 2017 which wouldn't interact in the collision in the first place due to is lack of density and charge. Even most of the hot plasma halo wouldn't directly collide or interact due to it's lack of density. That estimation method also underestimated the number of stars and their mass that is located between the galaxies in those clusters, and it ignores the fact that you've been underestimating the brightness/luminosity by a giant factor of two to start with!

That 2006 bullet cluster study only "proved"' that your M/L!=2 formula to calculate stellar and baryonic mass is ridiculously flawed and overly simplified to begin with.

Even the original study notes that the errors in estimating the baryonic mass in that study could be *huge*, even without the various revelation of stellar underestimates discovered since 2006.

The assumed mass-to-light ratio is highly uncertain (can vary between 0.5 and 3) and depends on the history of recent star formation of the galaxies in the apertures; however even in the case of an extreme deviation, the Xray plasma is still the dominant baryonic component in all of the apertures. The quoted errors are only the errors on measuring the luminosity and do not include the uncertainty in the assumed mass-to-light ratio.


Face it, you have *zero* evidence that your baryonic mass estimation techniques were worth the paper they were printed on in 2006, actually 2003, and in fact there is *ample* evidence that they were not ever accurate to begin with.

Your whole claim about the existence of non-luminous dark matter hinges upon your presumption that your baryonic mass estimation techniques were correct, and we now know for a fact that they were never correct and you've never corrected them either! Sheesh. You folks should be sued for false advertising. You have no evidence whatsoever that you can correctly estimate the amount of baryonic matter in a distant galaxy based strictly on a luminosity function, and we have ample evidence that you cannot!
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Aardwolf » Mon Jan 14, 2019 4:12 pm

Higgsy wrote:
Aardwolf wrote:However they are probably wasting their time as there is not likely to be any found in the lab when it's missing from the whole solar system.
Astrophysicists believe that our galaxy must be filled with more dark matter than ordinary matter. Now astronomers say they can find no evidence of dark matter’s gravitational influence on the planets. What gives?
https://www.technologyreview.com/s/516681/the-incredible-dark-matter-mystery-why-astronomers-say-it-is-missing-in-action/

Although as we know this stuff is magic, and possibly sentient, it's probably just playing hide and seek.
That's the trouble with reading popular articles and swallowing them whole without question. I know people here are averse to quantifying things but shall we do some sums? The article puts an upper limit on the mass of dark matter within a sphere of radius the orbit of Saturn of 1.7x 10-10 solar masses. So assuming the halo has uniform density (in fact the density at the Sun is less than the mean so this is a worst case), let's work out what the mass of the halo would be. The halo radius is approximately 53,000 light years. The radius of Saturn's orbit is 0.00015 light years. So the ratio of the two volumes is 53,0003/0.000153 = 4.4 x 1025. So the total halo weighs 4.4 x 1025 times the halo within a sphere with radius of Saturn's orbit. Multiplying the upper limit of the mass within tha sphere by that ratio gives a total mass for the halo = 4.4 x 1025 x 1.7 x 10-10 = 7.5 x 1015 solar masses. This is 1,000 times MORE than the estimated total mass of the halo which is of the order of 1012 solar masses. In other words , the sensitivity of the test is 1,000 times too low to be able to detect the dark matter by orbital perturbations in the solar system.

Another way of looking at this is that the paper claims an upper limit for dark matter density in the orbit of the Saturn of 1.1 x 10-20g cm-3. But the expected density of dark matter in the solar system is about 10-24g cm-3, ~10,000 times less. So of course the test isn't going to detect the influence of dark matter on the solar system, as it is much too little for the sensitivity of this test.

Only the authors can you tell you why they did a test and wrote a paper, when the prediction was that the test would be too insensitive by a factor 1,000 - 10,000. And you really need not to swallow popular articles on science whole.
As expected the go to response is to disparage the authors/messenger. Typical MO. So how do we know which appeal to authority to believe...however, 10-24g cm-3 seems low. Where did you get this from?
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Re: It's impossible to prove a negative.

Unread postby Aardwolf » Mon Jan 14, 2019 4:34 pm

Higgsy wrote:
Aardwolf wrote:My point is there is always exactly the right amount of dark matter, in exactly the right place, to create a flat rotational curve in a spiral galaxy. Why?
OK - that's a reasonable question.
Yes and it’s a shame you don’t answer it below.

Higgsy wrote:The first thing is that the rotation curves of spiral galaxies are not all exactly the same. They do vary from galaxy to galaxy.
When did I say they were? Strawman. I only state that whatever the size/density they ultimately create a flattened curve.

Higgsy wrote:The term flat rotation curve doesn't mean that the rotational speed of stars in a galaxy is constant as a function of radial distance from the centre. What it does mean is that the function of rotational speed versus radial distance does not decline with distance as quickly as would be expected if the only mass in the galaxy is baryonic mass (comprising stars detected in a range of bands, and gas and dust detected in HI and so on), and the rotation curve of one galaxy to the next is not exactly the same. However, the rotation curve of stars in spiral galaxies can be explained if there is a substantial quantity of undetected mass surrounding the galaxy and interacting gravitationally with the stars and interstellar gas and dust. Lensing studies have confirmed that this mass lies in a roughly spherical shape around spiral galaxies and this quantitatively explains the flat rotation curve. The matter in the spherical halo lies in a sphere whereas the stars and gas lie more on a disc, because the former is collisionless whereas the latter averages its angular momentum to zero except aroungd the vector where it had residual angular momentum in the first place. Typically the total galaxy mass within the stellar radius is 90% in the halo, 8% in stars and 2% in gas and dust. So there is no magic involved - the halo is roughly spherical and that explains the flat rotation curve in the disk without having to be exact.
So you’ve described the status of a galaxy, but you haven’t even attempted to explain why a given particular mass of dark matter attracts exactly the right amount of ordinary matter so that the density and ratio (of ordinary matter to dark matter) equates so that the vast outer region of the galaxy rotates uniformly to create the observed flattened curves. Then it stops attracting any more matter and maintains the density and ratio for billions of years. Explain why?
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Aardwolf » Mon Jan 14, 2019 4:50 pm

Higgsy wrote:
Aardwolf wrote:
Astrophysicists believe that our galaxy must be filled with more dark matter than ordinary matter. Now astronomers say they can find no evidence of dark matter’s gravitational influence on the planets. What gives?
https://www.technologyreview.com/s/516681/the-incredible-dark-matter-mystery-why-astronomers-say-it-is-missing-in-action/

And another thing is the ridiculous popular article you link to, which is pure sensationalist rubbish like popular science articles often are. It talks nonsense like "If the Sun is surrounded by a thick soup of dark matter". Thick soup indeed, when the expected local density of dark matter is about 0.5 proton masses per cm3. The author's no more numerate than the general run of people on the forum.
Is that more or less sensational rubbish than;

A DIRECT EMPIRICAL PROOF of the existence of dark matter - Honestly guv, this is the bestest most proofiest paper even written by humans or gods. Go home now, you can all quit looking. We won the science.

PS. You may want to contact MIT and inform them the magazine they are running is garbage.
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Higgsy » Mon Jan 14, 2019 6:37 pm

Aardwolf wrote:
Higgsy wrote:
Aardwolf wrote:However they are probably wasting their time as there is not likely to be any found in the lab when it's missing from the whole solar system.
Astrophysicists believe that our galaxy must be filled with more dark matter than ordinary matter. Now astronomers say they can find no evidence of dark matter’s gravitational influence on the planets. What gives?
https://www.technologyreview.com/s/516681/the-incredible-dark-matter-mystery-why-astronomers-say-it-is-missing-in-action/

Although as we know this stuff is magic, and possibly sentient, it's probably just playing hide and seek.
That's the trouble with reading popular articles and swallowing them whole without question. I know people here are averse to quantifying things but shall we do some sums? The article puts an upper limit on the mass of dark matter within a sphere of radius the orbit of Saturn of 1.7x 10-10 solar masses. So assuming the halo has uniform density (in fact the density at the Sun is less than the mean so this is a worst case), let's work out what the mass of the halo would be. The halo radius is approximately 53,000 light years. The radius of Saturn's orbit is 0.00015 light years. So the ratio of the two volumes is 53,0003/0.000153 = 4.4 x 1025. So the total halo weighs 4.4 x 1025 times the halo within a sphere with radius of Saturn's orbit. Multiplying the upper limit of the mass within tha sphere by that ratio gives a total mass for the halo = 4.4 x 1025 x 1.7 x 10-10 = 7.5 x 1015 solar masses. This is 1,000 times MORE than the estimated total mass of the halo which is of the order of 1012 solar masses. In other words , the sensitivity of the test is 1,000 times too low to be able to detect the dark matter by orbital perturbations in the solar system.

Another way of looking at this is that the paper claims an upper limit for dark matter density in the orbit of the Saturn of 1.1 x 10-20g cm-3. But the expected density of dark matter in the solar system is about 10-24g cm-3, ~10,000 times less. So of course the test isn't going to detect the influence of dark matter on the solar system, as it is much too little for the sensitivity of this test.

Only the authors can you tell you why they did a test and wrote a paper, when the prediction was that the test would be too insensitive by a factor 1,000 - 10,000. And you really need not to swallow popular articles on science whole.
As expected the go to response is to disparage the authors/messenger. Typical MO.

Bollocks. What a nonsensical comment. How can it be disparaging the authors to point out that their test is 1,000 to 10,000 times too insensitive to detect dark matter's effect on solar system orbits? It's just a fact. They say that the epherimedes constrain the dark matter mass to be less than 1.7 x 10-10 solar masses within a sphere of radius Saturn's orbit and everyone else says "we are not surprised - the mass is predicted to be a 1,000 times less than that".
So how do we know which appeal to authority to believe...however, 10-24g cm-3 seems low. Where did you get this from?
Easily calculated from halo mass and radius (1012 solar masses and 53,000 light years). But see also Salucci et al, The dark matter density at the Sun's location, A&A 523, A83, 2010.
Last edited by Higgsy on Mon Jan 14, 2019 6:54 pm, edited 1 time in total.
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Re: It's impossible to prove a negative.

Unread postby Higgsy » Mon Jan 14, 2019 6:53 pm

Aardwolf wrote:So you’ve described the status of a galaxy, but you haven’t even attempted to explain why a given particular mass of dark matter attracts exactly the right amount of ordinary matter so that the density and ratio (of ordinary matter to dark matter) equates so that the vast outer region of the galaxy rotates uniformly to create the observed flattened curves. Then it stops attracting any more matter and maintains the density and ratio for billions of years. Explain why?
What makes you think that a particularly tightly constrained stellar to DM ratio is needed to yield a flat rotation curve? In almost all spiral galaxies the DM halo dominates the total mass, and whether the ratio is 0.05 or 0.15, a roughly spherical halo will result in flat rotation curves. All you need is substantial mass away from the galactic centre. To the first order the ratio is given by the universal DM to baryonic matter ratio, recognising that stars and dust form only about 1% of the total mass and intergalactic hot gas forms about 10%. And since many star forming regions are found at the edge of galaxies, it seems that they don't stop growing.
"Every single ion is going to start cooling off instantly as far as I know…If you're mixing kinetic energy in there somehow, you'll need to explain exactly how you're defining 'temperature'" - Mozina
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Higgsy » Mon Jan 14, 2019 6:59 pm

Aardwolf wrote:
Higgsy wrote:
Aardwolf wrote:
]Is that more or less sensational rubbish than;

A DIRECT EMPIRICAL PROOF of the existence of dark matter - Honestly guv, this is the bestest most proofiest paper even written by humans or gods. Go home now, you can all quit looking. We won the science.
Shut up about the title and read and try to understand the sodding paper. Which contains neither rhetoric nor exaggration. I know, I know, it has some big words in it and you'd rather stick to the popular press.

PS. You may want to contact MIT and inform them the magazine they are running is garbage.
Not my problem bro, if you don't know how to distinguish between science ad sensationalism.
"Every single ion is going to start cooling off instantly as far as I know…If you're mixing kinetic energy in there somehow, you'll need to explain exactly how you're defining 'temperature'" - Mozina
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Re: Lambda-CDM - EU/PC Theory - Confirmation Bias

Unread postby Aardwolf » Tue Jan 15, 2019 8:35 am

Higgsy wrote:
Aardwolf wrote:
Higgsy wrote:
Aardwolf wrote:However they are probably wasting their time as there is not likely to be any found in the lab when it's missing from the whole solar system.
Astrophysicists believe that our galaxy must be filled with more dark matter than ordinary matter. Now astronomers say they can find no evidence of dark matter’s gravitational influence on the planets. What gives?
https://www.technologyreview.com/s/516681/the-incredible-dark-matter-mystery-why-astronomers-say-it-is-missing-in-action/

Although as we know this stuff is magic, and possibly sentient, it's probably just playing hide and seek.
That's the trouble with reading popular articles and swallowing them whole without question. I know people here are averse to quantifying things but shall we do some sums? The article puts an upper limit on the mass of dark matter within a sphere of radius the orbit of Saturn of 1.7x 10-10 solar masses. So assuming the halo has uniform density (in fact the density at the Sun is less than the mean so this is a worst case), let's work out what the mass of the halo would be. The halo radius is approximately 53,000 light years. The radius of Saturn's orbit is 0.00015 light years. So the ratio of the two volumes is 53,0003/0.000153 = 4.4 x 1025. So the total halo weighs 4.4 x 1025 times the halo within a sphere with radius of Saturn's orbit. Multiplying the upper limit of the mass within tha sphere by that ratio gives a total mass for the halo = 4.4 x 1025 x 1.7 x 10-10 = 7.5 x 1015 solar masses. This is 1,000 times MORE than the estimated total mass of the halo which is of the order of 1012 solar masses. In other words , the sensitivity of the test is 1,000 times too low to be able to detect the dark matter by orbital perturbations in the solar system.

Another way of looking at this is that the paper claims an upper limit for dark matter density in the orbit of the Saturn of 1.1 x 10-20g cm-3. But the expected density of dark matter in the solar system is about 10-24g cm-3, ~10,000 times less. So of course the test isn't going to detect the influence of dark matter on the solar system, as it is much too little for the sensitivity of this test.

Only the authors can you tell you why they did a test and wrote a paper, when the prediction was that the test would be too insensitive by a factor 1,000 - 10,000. And you really need not to swallow popular articles on science whole.
As expected the go to response is to disparage the authors/messenger. Typical MO.

Bollocks. What a nonsensical comment. How can it be disparaging the authors to point out that their test is 1,000 to 10,000 times too insensitive to detect dark matter's effect on solar system orbits? It's just a fact. They say that the epherimedes constrain the dark matter mass to be less than 1.7 x 10-10 solar masses within a sphere of radius Saturn's orbit and everyone else says "we are not surprised - the mass is predicted to be a 1,000 times less than that".
It's what you say not everyone else and pointing out "facts" can be disparaging, the two are not mutually exclusive. You're stating their work was a waste of time.

Higgsy wrote:
So how do we know which appeal to authority to believe...however, 10-24g cm-3 seems low. Where did you get this from?
Easily calculated from halo mass and radius (1012 solar masses and 53,000 light years). But see also Salucci et al, The dark matter density at the Sun's location, A&A 523, A83, 2010.
The halo has a radius of only 53,000 light years? So it's smaller the than the milky way itself?
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