What Do We Know For Certain?

[Aardwolf]

Aardwolf,

What force or exchange of momentum accelerates light when it exits a denser medium?

I was not aware that light is accelerated anywhere. Surely it always travels at c (other than the Aardwolf caveat of course). Photons/light travel at c in "the vacuum" and slower through other mediums. I would say that it is due to absorption (i.e. collision) with electrons and then re-emission. As to the speed it travels (future evidence notwithstanding) it always travels at the same speed and always actually travels through the vacuum.

Why do you ask?

You acknowledge that it slows through other mediums, but if energy/momentum can only be transfered what is causing light to regain its higher propagation speed (I agree accelerate is the wrong word as it's a discrete increase) upon exiting said denser material?

[mjv1121]

Aardwolf,

As I said, it always travels at the same speed and only ever travels through the vacuum. Time spent on absorption and re-emission is the reason for slower apparent progress, but the speed of travel is constant.

Michael

[tayga]

Since you mention Newton, and since it is his laws to which I am referring, perhaps we may ask his opinion:

...so that one body may act upon another at a distance, through a vacuum, without the mediation of anything else, by and through which their action and force may be conveyed from one to another, is to me so great an absurdity, that I believe no man who has in philosophical matters a competent faculty of thinking can ever fall into it."

The possibility of effect without cause such as that required by force or action at a distance is utterly absurd.

I have never said I disagree with this. How did you infer that I think that force is not conveyed from one object to another? How do you justify discounting an ether, for example?

The purpose of this thread is to divine, beyond the bleeding obvious of 1)-5), what we can say that we know rather than what we think we know...

I'll echo the comment above: you don't seem to have done that in points 1) to 5).

... self-evident

That was just to annoy me, right?

[webolife]

Aardwolf,
You are correct about the BEC. I misspoke by juxtaposing my statement about that right after my statement about refraction. However the delay of the light signal measured in the electrically confined cloud medium may be due to the slow retransmission of the collimated light signal due to the unique electrically aligned state of the BEC. By the time the signal is received, the inertial response of individual atomic array of/within the BEC has been overcome. So the signal delay suggests that light stuff is moving but does not actually demonstrate it.

MJV,
Do I misunderstand you to be saying that light only ever moves through a vacuum? How does it then get through the glass of my light bulb or window, or the radio signals through the wall of my house? By what mechanical means do you explain this? Are you saying that the light signal energy is somehow [mostly] conserved across a medium such as a solid piece of glass, but does not move through it? Or are you trying to say that a vacuum is composed of densely packed quantums that somehow transmit the light signal? Help me out here.

[mjv1121]

webolife,

Do I misunderstand you to be saying that light only ever moves through a vacuum?

I am suggesting, that a photon (particle or wave, the choice is yours) is only ever travelling (i.e. traversing distance) through the vacuum. In a medium such as air or glass, the photon is periodically intercepted by an electron and then re-emitted as a brand new photon with wavelength/frequency properties as dictated by the atomic spectroscopic characteristic of the given medium. In between the pesky electrons, that slow the light's progress, is vacuum - in fact most of the glass or air is vacuum. From the photon's perspective it travels through the vacuum until intercepted, it then passes the baton, so to speak, to a new photon to continue the journey, but whilst actually travelling it is travelling through the vacuum at a constant speed (invoke Aardwolf caveat).

I would suggest that "the vacuum" is in fact an aether. You detail this as a "universal unified force/pressure field". I would detail it an a quantum particle field (although I may refer to it as quantum vacuum field, quantum field or simply "the vacuum"). Obviously the nature of the underlying quantised aether is rather too speculative to be included in a list of things we "know".

(As an interesting aside, I have proposed that Alpha (the fine structure constant) is the density of the quantum field. There is a recent thread in "Electric Universe" entitled "Nature's laws may vary across the Universe", which suggests that alpha may vary across the universe. This could lead to very interesting implications.)

Michael

[webolife]

MJV,
Ok, I think I do understand you correctly then.
Would you agree, no, can you understand, my view that unless light is intercepted/retransmitted/detected by some substantial means, there is actually nothing we know about its behavior in the "vacuum" between such interactions?

So if I propose that light action is instantaneous in that vacuum, or you propose that it travels at the c-rate [as a particle/wave/you choose] across that vacuous medium [oxymoron?], that either is possible based on the observations? By the way, I do not choose traveling photons of either wave or particle or dual nature. I do not say that light or gravity travels at infinite speed, that would be absurd. What I say is that the light action between source and receiver is instant, as both the source and receiver are members of the same universal field. The only action required is for the "electron" to "drop" at the source, and for my eye to be open so my photoreceptor cell can register the potential drop of the field in that direction. Nothing has to travel or collide in the intervening space, only at the source site, and in the resonant photoreceptor cell, to make this happen. That is an entirely different physical paradigm from yours [and most folks ], and is why I am discussing this issue on your thread about things we know for sure.

[mjv1121]

webolife,

Would you agree, no, can you understand, my view that unless light is intercepted/retransmitted/detected by some substantial means, there is actually nothing we know about its behavior in the "vacuum" between such interactions?

Yes, I understand your view on this. All we know about "photonic phenomena" (I hope this is sufficient to accommodate both of us) is that which occurs between its latest (this is for me) emission and our detection. We may infer more knowledge via theory, but we do not know.

Nothing has to travel or collide in the intervening space, only at the source site, and in the resonant photoreceptor cell, to make this happen.

I do not believe you have stated this entirely correctly - either that or there is a gaping hole in your theory. Surely, there must be some "signal" that communicates between source and destination, else how does your "photoreceptor cell....register the potential drop of the field in that direction"?.

Regardless, of the above, effect has cause. I re-state by list for your agreement or criticism.

What We Know To Be True:

1) A body will remain at rest or in uniform motion unless acted upon by an external force. This might also be summarised as all effects must have a cause. This also serves as proof that action at a distance is not possible.
2) All actions have an equal and opposite reaction.
3) Momentum cannot be created or destroyed, it can only be transferred. This might also be summarised as the conservation of momentum and by extension, the conservation of energy.
4) Force can only be generated by collision. This might also be stated as force is the act of collision. This also serves as further proof that action or force at a distance is not possible.
5) Anything that can affect the physical universe must be considered to be physical. This might also be stated as anything physical constitutes a form of matter.
6) The entropy of an isolated system never decreases.

Michael

PS I still fail to understand is the physical nature of your "universal field".

[webolife]

Yes, I understand this is an entirely different paradigm than you are accustomed to.
Because the field is in fact [oops, according to my belief] universal, my peripheral position in the field and the source's locus in the field are connected. Think of it as potential... voltage... detected as light... as a vectoral push toward the centroid [aka light source]. It physically pushes on my retina from behind in the direction of the lamp, candle, sun or star. It, ie the light field, is measurable as pressure [take a radiometer for example], and illustrated readily by optical ray diagrams, because its physical nature is in fact [oops again] optical vectors, a force field. The field acts upon, is detected by these interactions upon, and is measured by its effect upon particles. The field is physically observable as the spectrum elicited through any prismatic or slit device, such as raindrops, a spectroscope, or my eye which enables the vectors to be ordered/arrayed as a pressure gradient with respect to the central line of sight. This is its physical nature, observable, illustrable, photographable vectors of pressure, and accessible to anyone who can look. And to top it off, this pressure field is also the cause of gravitation, vectors of pressure aimed at the centroid of the local system, and as previously analogized also the source of electricity [the EU folks here say it is electricity]. As is also true of your quantums, the origin and fundamental motor of the mechanism is beyond the reach of materialistic science.

And a statement that force comes about only through collisions of particles cannot be proof that action cannot happen at a distance, since it is restating the premise.

[mjv1121]

webolife,

As is also true of your quantums, the origin and fundamental motor of the mechanism is beyond the reach of materialistic science.

This is not so. You may consider my quantums to be tiny spheres moving at c - each has a mass 1.47x10^50 kg and therefore a linear kinetic energy of 6.63x10^34 J (which is Planck's constant, h). There are at least 4.95x10^47 quantum particles in every cubic metre of the universe.

Your question may be, what makes them move? I have said that they have been in motion for "a very long time". If we take it for granted that we and the universe exists, and I think we must else this entire endeavour is pointless, we must assume that the universe has existed, in some form or other, for an infinite amount of time in the past and will exist for an infinite amount of time in the future. We may suppose then that the universe as we know it is due to an event or events or a process that occurred at some unknowable time in the past and which we may also suppose to be a very long time ago. This event or process that "created" the quantum field would also have created spinning electrons and spinning protons. Thus the entire universe and all the momentum contained in it, is a legacy of an unknowable past. Continued operation of the universe is simply by conservation of momentum. Any questions?

A randomly moving material particle field, together with electrons and protons, readily provides the opportunity to explain the operation of the observable universe. That said, such a system, and the world and universe we "observe", operates with a certain amount of complexity, making proof rather difficult to achieve especially from such a young theory. Even, if in due course, I were able to give detailed process explanations, back by consistent mathematical explanations, by a scientific necessity I would still only be able consider such a result as "probably true". It would even then not qualify as "what we know for certain".

a statement that force comes about only through collisions of particles cannot be proof that action cannot happen at a distance, since it is restating the premise.

Effect requires cause. Force, which may for these purposes by considered synonymous with action, is in these terms an effect. Force requires cause. Since force can only be imparted by contact, force may be considered to be the result of contact, that is, force is the result of collision, since collision is contact. If force cannot be applied without contact then force cannot be applied at a distance. The only premise restated is that effect requires cause.

What We Know To Be True:
1) A body will remain at rest or in uniform motion unless acted upon by an external force. This might also be summarised as all effects must have a cause. This also serves as proof that action at a distance is not possible.
2) All actions have an equal and opposite reaction.
3) Momentum cannot be created or destroyed, it can only be transferred. This might also be summarised as the conservation of momentum and by extension, the conservation of energy.
4) Force can only be generated by collision. This might also be stated as force is the act of collision. This also serves as further proof that action or force at a distance is not possible.
5) Anything that can affect the physical universe must be considered to be physical. This might also be stated as anything physical constitutes a form of matter.
6) The entropy of an isolated system never decreases.

Michael

[Sparky]

-for an infinite amount of time in the past and will exist for an infinite amount of time in the future.-

I am very uncomfortable with , "an infinite amount of time".

I will compromise with you and accept an amount of time equal to 1/2 infinity.....

[webolife]

I caught that too, Sparky, but I'll assume that Michael meant to say indefinite.
MJV, you said "that is not so" to my statement that the origin of the field's properties was beyond the reach of materialistic science, then after a lengthy defense of your view about how old the universe must be, concluded that the origin is "unknowable"; I'll take that as a restatement of "beyond [your] reach." You cannot alter the circularity of the cause and effect issue by defining the force as an effect, but elsewhere saying that the effect [colliding particles] causes force. At some point you have to admit that you don't know or don't have the prime mover, at which point your argument becomes moot. I say the universal force field causes the motions of everything, you say the motions of everything causes the force[s]. Our descriptions thereupon of the physics of the universe will proceed differently.
But let me pose another question for you: Your quantums if I understand correctly [it bothers me that you don't use the conventional 'quanta' as the plural] are for you "solid" objects that physically "touch" each other in a collision, some at extremely high speed. Explain what you are thinking when your particles "touch" and how can you justify this type of actions at the fundamental level and end up with anything but chaos and destruction as your resultant universe? After all, the entropy of an isolated system never decreases...

[Sparky]

"solid" objects that physically "touch"

what is a particle? what is mass? I'm looking at water in a lake. It has molecules. Look more microscopically, and it is mostly empty space, being infused with a phield of ??? Below the level of a molecule it is not called water. Below the level of an atom it is not called an element of some sort. So, it changes from a liquid, gas, or solid to "particles", interacting with other particles. At some point, what we call solid, particles, mass, gets really small, and the definition of solid, or particle seems to blur with mass being measured electrically, but given a "weight", particles having a charge or being neutral, and solid becomes the pure repulsive charge that particles feel when they interact intimately.

Vibrations are inherent. Why? The more energy transfered the higher the vibrations. The smaller the particle. We measure frequencies here, then look at how they have shifted from a distant galaxy and deduce all sorts of things from that shift.
It is all electrical, but we call it matter.

We have this Planck thing... If there is a possibility of a sub-Planck, would there be particles? Could there be a point where "electrical charge" can not exist? The universe and all it's electrical phenomenon would be built upon a complex substratum of [To be continued at a later time]

[mjv1121]

webolife,

As is also true of your quantums, the origin and fundamental motor of the mechanism is beyond the reach of materialistic science.

I took this to mean that you have no idea how your universal field generates motion and that neither do I with my quantum field; hence my reply. If instead by "origin and fundamental motor of the mechanism" you meant how did the universe start, then I say again I am happy to ignore that information as unknowable. The universe is here now and is working, and we may presume has been working for a long time. That we do not know how or when it started in its present form does not mean we cannot analyse its present mode of operation.

You cannot alter the circularity of the cause and effect issue by defining the force as an effect, but elsewhere saying that the effect [colliding particles] causes force

The use of the word "effect" is, I admit, somewhat clumsy, because it is both noun and verb: "The effect of collision is to produce an effect of force." I will try again: "The result or consequence of collision is to cause the effect of force".

Effect requires cause. Force, which may for these purposes by considered synonymous with action, is in these terms the effect. Force requires cause. Since force can only be imparted by contact, force may be considered to be the result of contact, that is, force is the result of collision, since collision is contact. If force cannot be applied without contact then force cannot be applied at a distance. The only premise restated is that effect requires cause.

Explain what you are thinking when your particles "touch"

Due to the density of the field and the size of the quantum particles, I do not envision that they would collide very often. If and when they did it would simply be a mutual change of direction. The "shape" of the field would not change, since the motion is homogeneously random.

What We Know To Be True:
1) A body will remain at rest or in uniform motion unless acted upon by an external force. This might also be summarised as all effects must have a cause. This also serves as proof that action at a distance is not possible.
2) All actions have an equal and opposite reaction.
3) Momentum cannot be created or destroyed, it can only be transferred. This might also be summarised as the conservation of momentum and by extension, the conservation of energy.
4) Force can only be generated by collision. This might also be stated as force is the act of collision. This also serves as further proof that action or force at a distance is not possible.
5) Anything that can affect the physical universe must be considered to be physical. This might also be stated as anything physical constitutes a form of matter.
6) The entropy of an isolated system never decreases.


Michael

PS I was aware of my double infinity, but I reckon infinity times infinity equals infinity rather than infinity squared, hence I see no logical or grammatical error in using a split infinity.

[webolife]

Due to the density of the field and size of the particles and sparsity of collisions, how do they then confer cause and effect across the distance of the field?

My problem with your "infinity" was its juxtaposition with the word "amount". Oxymoron. There is either an amount or it is infinite. I say there IS an "amount" [both in minimum and maximum size, and number of particles, and therefore the space between them, notwithstanding the concept of "time"], therefore it is not infinite.

[jjohnson]

Hi, mjv1121,

I am pretty sure (but not certain) that I am not certain about almost everything. A recent exception is that I am pretty sure that you are very certain indeed. Can you be certain you are correct if that belief does not fall under one of your six categories of things you are certain are true, or truisms?

An interesting and insightful read might be, On Being Certain: Believing You Are Right Even When You're Not, by Dr, Robert Burton, M.D.

Jim