Heat conduction in solids: Why is it so slow?

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Heat conduction in solids: Why is it so slow?

Post by Tim_BandTechDotCom » Sat Nov 20, 2010 7:57 pm

I've started discussing this topic here on the LHC portal over at
viewtopic.php?f=5&t=745
but have been asked to leave that thread alone.

Basically, I am challenging the modern interpretation of heat flow as 'vibrating atoms' or in Feynman's words 'jiggling atoms':
http://www.youtube.com/watch?v=v3pYRn5j ... re=related

This interpretation lacks an explanation of how heat can come to travel so slowly through solid materials. For instance compare the flow of heat through glass to the flow of acoustic energy through glass. Really, any solid material will do, and perhaps it is best to use a crystalline form as the model. Even the finest conductors of heat such as aluminum or copper are ridiculously slow in their heat conduction relative to the rate of propagation of sound through those same materials.

I propose that the modern interpretation of heat as vibrating atoms is flawed, and that rotation is a more likely explanation, for it may be possible to introduce nuclear rotation as a well isolated means of energy storage, though the rotational moment cannot be so small. There was a time when people simply admitted that they did not fully understand the explanation of well behaved phenomena such as heat flow; when people like Maxwell attempted coherent interpretations. Modern physics would have us believe that those times are gone, but I don't think so.

Kinematics in a crystalline solid do not seem to provide enough room for two modes of such discrepant nature as heat and sound, yet that sound is vibrating atoms and that heat is vibrating atoms is accepted by the modern scientist. Why? If the modern scientist is incapable of explaining why the same description holds for two very different phenomena then what of modern science?

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Re: Heat conduction in solids: Why is it so slow?

Post by Kasuha » Sun Nov 21, 2010 8:45 am

The reason why speed of sound is so different from speed of heat is in wave mechanics.
In your previous example with a crystal kept at perfect zero temperature, if you move one atom, the effect of this change will propagate through the body of the crystal at maximum speed, but the amplitude of the change will vanish very quickly - with square of the distance. If you at the same time move neighbor atom the other way, it will propagate at the same speed along it and it will mostly cancel out the change caused by the first atom movement. These two atoms can continue jiggling at their places keeping relatively high heat at the place where they are, provoking resonances all over the crystal which are so small that you'll be unable to measure them.
Heat spot on your crystal is exactly that - it's a place where atoms move chaotically in all directions, "shaking" the crystal but mostly cancelling out all generated waves. It's a standing wave. Check this video at time 0:11-0:36 for an example what I mean (note that the video is about something else and not necessarily correct, I only refer to the image).
Sound is not a standing wave. It is wave running through the body of the crystal and as long as its wavefront goes through the whole mass of the crystal its amplitude does not decrease (amplitude from each individual atom decreases with square of the distance, but amplitudes from all atoms that contribute add up on the front of the wave and cancel out on its back).

Even if you don't accept this explanation, rotation does not solve your mystery. For all practical purposes in physics atoms are featureless and don't really rotate. In nuclear and particle physics you can find some features on atoms but still the rotation does not make much sense because rotation consists of something running around something else which does not happen in atoms.

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Re: Heat conduction in solids: Why is it so slow?

Post by chelle » Sun Nov 21, 2010 9:24 am

I think that you are seeing things far too complicated, if you have a series of domino's and you tip one over, a wave is generated, if you let one domino rotate or vibrate the transition of energy/heat won't be as instand as with the push. Things do become more complicated when you presume there is an aether.
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Re: Heat conduction in solids: Why is it so slow?

Post by Tim_BandTechDotCom » Mon Nov 22, 2010 4:03 pm

Kasuha wrote:The reason why speed of sound is so different from speed of heat is in wave mechanics.
In your previous example with a crystal kept at perfect zero temperature, if you move one atom, the effect of this change will propagate through the body of the crystal at maximum speed, but the amplitude of the change will vanish very quickly - with square of the distance. If you at the same time move neighbor atom the other way, it will propagate at the same speed along it and it will mostly cancel out the change caused by the first atom movement. These two atoms can continue jiggling at their places keeping relatively high heat at the place where they are, provoking resonances all over the crystal which are so small that you'll be unable to measure them.
Heat spot on your crystal is exactly that - it's a place where atoms move chaotically in all directions, "shaking" the crystal but mostly cancelling out all generated waves. It's a standing wave. Check this video at time 0:11-0:36 for an example what I mean (note that the video is about something else and not necessarily correct, I only refer to the image).
I'm sorry Kasuha, but the chaotic nature of this description is nonexistent. If we construct your mode, so that atoms are symmetrically bonded to their nearest neighbors then the ability to isolate the behavior of one atom with just one of its neighbors is not granted. To simplify we could consider the one dimensional case, then extend upward to three dimensions. So along a line we see atoms on intervals. What we see is exactly your standing wave description. What you have constructed is an acoustic wave whose wavelength is two atomic diameters. Yes, it is very tight, but now if we damp one end of the line of atoms (extend upward in dimension to a rod of the same material) how quickly shall we see the result at the other end of the rod? So the position of the last atom in the line (at the end of the rod) is now fixed or forced. When its neighbor attempts to move away the fixture will be pulling through the end atom in the opposite direction. Because all of the atoms are connected we can simply extend this action symmetrically down the chain, and we see a rapid means of dissipating the energy. A type of matter which does not have this behavior will not be a solid. If we do not grant the interaction of one atom to all of its neighbors then we are committing a fraud. I do not mean to call you a fraud though, for you are attempting to provide a resolution. I thank you, but I do not see that this is convincing.
Sound is not a standing wave. It is wave running through the body of the crystal and as long as its wavefront goes through the whole mass of the crystal its amplitude does not decrease (amplitude from each individual atom decreases with square of the distance, but amplitudes from all atoms that contribute add up on the front of the wave and cancel out on its back).

Even if you don't accept this explanation, rotation does not solve your mystery. For all practical purposes in physics atoms are featureless and don't really rotate. In nuclear and particle physics you can find some features on atoms but still the rotation does not make much sense because rotation consists of something running around something else which does not happen in atoms.
I partially agree with your statement above. It is true that atoms have not been regarded as containing rotational momentum. All of the mass has been placed at the center of the atom. And so the rotational model of heat not only addresses a flaw in the interpretation of thermodynamics; it also exposes another possible flaw; that the atomic model may be wrong. Isn't it a bit too convenient that the atoms mass is at its center of mass?

Rutherford's gold foil experiment is regarded as the turning point toward the nuclear model that still is maintained today. I don't find that experiment very convincing. As far as I can tell he never even proved any repulsive nature of the alpha particle. Anyway, this all will seem tangential to the core argument, and so I return to the initial problem.
Why does heat flow so slowly?

Thank you Kasuha for you attempt. I do not believe that you will find this discussion in any text on thermodynamics. Why? I'm not sure exactly why this is, but the idea that beliefs are falsifiable, and that we are not trained in falsification, but instead are trained in mimicry; these things I have become comfortable with.

I find it interesting that there are some possibilities to do with coherent heat flow.
Along a thermocline in say a thin sheet of material we can consider coherent rotations. For instance in a sheet of graphene one atomic layer thick we should see the following rotational pattern that leads to high thermal conductivity, and likewise forms interesting domains both in the axis of those rotations and along the sympathetic mode. To construct this theory I'll make a hot side and a cold side of this sheet, and simply model the atomic rotations as CC for counter clockwise and CW for clockwise:

[hot] CW CC CW CC CW CC CW CC CW CC [cold]

Now, in reality, these rotations may be more like a clock spring, so that they are actually oscillators. So long as we remain in the solid state then we should actually be able to do quite alot of math based on thermal mass and the temperature gradient. Again I stress that the rotational model works so well because the interactions can be loosely coupled. The phase relationships of the above domains is not granted; it is just the means of interaction that is exposed such that there is sympathetic rotation taking place. The trouble seems to me to be that the heat source has to be coherent in order to get this coherent form of heat flow. There are so many ways to generate heat that it is ridiculous to deny this possibility under the rotational theory of heat, and this would be new physics that can be predicted as a result of challenging the old heat model. This has to be done as cold physics, and there are already a number of surprises down there. Could it be that this method will help explain some of those phenomena?
If the coupling can be improved, then that will be some valuable material.

- Tim

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Re: Heat conduction in solids: Why is it so slow?

Post by Kasuha » Mon Nov 22, 2010 4:30 pm

As I wrote before, if you don't try to understand the real physics nature of events and insist on your own physics instead, you should have created this topic in Controversial Topics section. There are more people who reject reality and substitute their own in there.

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Re: Heat conduction in solids: Why is it so slow?

Post by CharmQuark » Mon Nov 22, 2010 6:08 pm

I shall move this to the Controversial Topics.

:) have fun discussing ;)
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Re: Heat conduction in solids: Why is it so slow?

Post by Tim_BandTechDotCom » Tue Nov 23, 2010 1:01 pm

Kasuha wrote:As I wrote before, if you don't try to understand the real physics nature of events and insist on your own physics instead, you should have created this topic in Controversial Topics section. There are more people who reject reality and substitute their own in there.
Kasuha, the pairing of atoms that you suggest as self cancelling cannot be the accepted mode of vibration. Where will I read of this?

Also I did follow the link you gave and watched quite alot of Ray Tome. He seems to be a good thinker. I am attracted to the standing wave theory, but once posed a question to Milo Wolf on it which challenges the standing wave theory. Waves generally dissipate their energy; as do sound and heat. So standing waves are typically set up in a reflective medium, whereby the energy does not dissipate, as you have done in the theoretical rod of material under discussion. These guys are essentially granting a standing wave, whereas I would like to see a theory which develops stability more naturally.

I don't think that the reflective argument can be used within the heat propagation problem. If we go this way then we could look at heat as infrared radiation, but then we have raised the discrepancy in propagation from speed of sound up to speed of light versus the rate of heat flow, with no mechanism to hold the heat. This radiation problem, even down into the cold, is not well addressed within the 'vibrating atoms' interpretation either. Heat as vibrating atoms is a big copout; one that has been absorbed and accepted by our humans. That science hoodwinks us much as religion does; well, we are humans and this is the common denominator. We are social beings and without mimicry we would not be able to communicate here. Those who fail to mimic are failures, especially within mathematics and physics.

Anyway, we've discussed this topic. I've been hoping to get more participation than just you and a moderator. It doesn't look like it's going to happen here at the CERN LHC portal.

Thanks, Kasuha for your participation. I think the string of atoms means of study exposes that you've isolated out pairs of atoms even though that isolation does not exist; at least not within a crystalline solid. Correcting this so that the atoms are symmetrically interacting with their nearest neighbors then yields rapid propagation, which is consistent with the propagation of acoustic energy but is inconsistent with the slow propagation of heat energy.

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Re: Heat conduction in solids: Why is it so slow?

Post by chelle » Tue Nov 23, 2010 1:46 pm

Tim_BandTechDotCom wrote:Along a thermocline in say a thin sheet of material we can consider coherent rotations. For instance in a sheet of graphene one atomic layer thick we should see the following rotational pattern that leads to high thermal conductivity, and likewise forms interesting domains both in the axis of those rotations and along the sympathetic mode. To construct this theory I'll make a hot side and a cold side of this sheet, and simply model the atomic rotations as CC for counter clockwise and CW for clockwise:

[hot] CW CC CW CC CW CC CW CC CW CC [cold]
You have an interesting point that there is rotation, but what you say doesn't make a lot of sense, check this clip if you would like to observe CW CC etc interaction: http://www.youtube.com/watch?v=wJqVhvTWqUM

If nuclei turn they would be like spinning tops and the direction of the spin wouldn't have the importance that you would like it to be, and it also wouldn't matter if it's expressed as a vibration or Jiggle, Just like a spinning washing machine vibrates, anyway check these Beyblade clip: http://www.youtube.com/watch?v=Zj963JlihdE
Tim_BandTechDotCom wrote:These guys are essentially granting a standing wave, whereas I would like to see a theory which develops stability more naturally.
I'm working on one, just be patient :shifty:
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Re: Heat conduction in solids: Why is it so slow?

Post by Kasuha » Tue Nov 23, 2010 3:42 pm

Tim_BandTechDotCom wrote:Kasuha, the pairing of atoms that you suggest as self cancelling cannot be the accepted mode of vibration. Where will I read of this?
In This video you can see a few modes of standing wave on a circular membrane. If such membrane was placed in vacuum and it was not losing energy by heating itself up it could continue in such motion after initial impulse forever.
In 3D space standing waves are possible as well, they're just harder to visualize.
Atoms do not need to be placed in vacuum, they already are in vacuum - gasses are just other atoms and inside a solid body there's very few of them, so you can imagine an inside of solid body as a mesh (a 3D "membrane") of atoms placed in vacuum. They also don't lose energy by heating because they don't really care how we call their motion.
Standing waves are reality and in fact they're quite common.

Also, this video shows how a wave that is apparently propagating can be created as a sum of standing waves.

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Re: Heat conduction in solids: Why is it so slow?

Post by tswsl1989 » Tue Nov 23, 2010 4:59 pm

Tim_BandTechDotCom wrote:Anyway, we've discussed this topic. I've been hoping to get more participation than just you and a moderator. It doesn't look like it's going to happen here at the CERN LHC portal.
We're a resonably small community, not everyone wants to get involved with this sort of discussion.
Haveing discussed this topic with you in the previous thread, I saw no reason to repost here.

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Re: Heat conduction in solids: Why is it so slow?

Post by chelle » Tue Nov 23, 2010 6:18 pm

Kasuha wrote:In This video you can see a few modes of standing wave on a circular membrane. If such membrane was placed in vacuum and it was not losing energy by heating itself up it could continue in such motion after initial impulse forever.
That's the question not losing energy. I don't think it would be possible, the strains on such a thing would differ all over the formation leading to deformation.
Kasuha wrote:Atoms do not need to be placed in vacuum, they already are in vacuum
Says who?

btw check this clip of 'resonance': http://www.youtube.com/watch?v=sY6z2hLgYuY

look at about 1:08 - Going round and round like weathercocks - ACW & CW directions :)
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Re: Heat conduction in solids: Why is it so slow?

Post by Kasuha » Tue Nov 23, 2010 8:12 pm

Chelle wrote:
Kasuha wrote:Atoms do not need to be placed in vacuum, they already are in vacuum
Says who?
If you don't think that's true tell me - what remains if you remove all atoms?

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Re: Heat conduction in solids: Why is it so slow?

Post by chelle » Tue Nov 23, 2010 8:47 pm

Kasuha wrote:
Chelle wrote:
Kasuha wrote:Atoms do not need to be placed in vacuum, they already are in vacuum
Says who?
If you don't think that's true tell me - what remains if you remove all atoms?
Aether (http://en.wikipedia.org/wiki/Luminiferous_aether) well accepted in classical physics.

The Michelson-Morley experiment (http://en.wikipedia.org/wiki/Michelson- ... experiment) only suposetly proved that there isn't moving Aether, making light move faster or slower, that doesn't mean there is no Aether. If you let 2 fish swim in opposite directions does this mean there is no water? If you let them swim in an a flowing river or sea, don't they travel the same distance in spite of the current of the water?
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Re: Heat conduction in solids: Why is it so slow?

Post by Tim_BandTechDotCom » Thu Nov 25, 2010 3:19 pm

Well, I watched all of the videos.

I love the tops, Chelle. They seem to be loosely coupled. It's quite a dance.

Also enjoyed the acoustic dust experiment, though I suspect the rotation there is a side effect of the transducer.

Under the model that I propose the interaction amongst the nuclei is minimal. I say 'nuclei' only because this is the standard atomic model, and if we are to store rotational energy in large amounts, then the nucleus concept is out, unless we are discussing ridiculous rotational velocities. We have specific heats of materials, and these translate to energy storage. Like say we heat up a block of aluminum. Using
http://www.ptable.com/
we see Al has a specific heat of
904 Joules per kilogram Kelvin,
and a thermal conductivity of
235 Watts per meter Kelvin

As I recall, 1 Kelvin is 1 Celsius in terms of a delta, which is what we are discussing. To get any realistic temperature difference we'd like something more than one degree, so how about 50 degrees of temperature rise. That's 45,200 Joules for a 1kg block, to raise its temperature, say from ambient up 50 degrees C.

If we instead considered conduction of heat we could hold one end of a rod(say a 1kg one meter long rod) at +50C from ambient, and hold the other end at ambient, and we should see that we are passing 4.7 Watts of heat energy through the rod steadily. That's not much power. Now the energy contained in the rod due to the temperature difference is half of the previous figure( we have a linear thermocline), so that we are discussing 22,600 Joules ( Watt seconds ), or 6.28 watt hours, so that to pass the amount of energy that the rod contains thermally( relative to ambient) will take about 1.33 hours in this steady state condition. I admit that this is not a great calculation, but it may be one that we can compare against acoustic energy. Also I am open to having made some mistakes here, so please correct this if I am in error.

It is the slowness of the interaction of heat that I am after, and at the atomic level things happen very quickly due to the short distances. The theory of rotation depends upon a lack of interaction to succeed, so that the tops in Chelle's video link are more locked into a lattice. The means of interaction is still a bit weak, but to suppose that there is interaction between the electron shells and the nucleus is believable, for if there were no interaction there could be no atomic model. It's a tough argument here to partially state that this theory may contaminate the nuclear model, and then to lean upon that nuclear model within the argument. I do see this as a weakness of my construction and that it needs its own atomic model to carry on, for all of the mass of the atom is currently claimed to be at its center of mass. This is a confluence that I am skeptical of. Should it be true that when a fundamental is broken that the resulting side effects are large then we should be more careful as to how far beyond the fundamentals we go with theory.

When one attacks an existing theory without a replacement theory then the position is weakened, but that does not invalidate the falsification of the existing theory. Still, there must be a clean replacement theory. Let's not forget how much revolves around temperature. There is thermal expansion, states of matter, and at cold temperature all of the most interesting recent physics, whose clean explanation may be partially miffed by a poor understanding of heat. The standing definition can only be called a fraud if it has been perpetuated for some ulterior purpose. The thing is, as to who determines the truth, well, they have already spoken... So do they determine the truth? No, they do not. Ultimately each individual is still burdened to seek out the truth, which includes seeking flaws in existing theory, if one practices upon those theories. Otherwise what we have is more religion than it is science.

Now I know most will think that I've gone too far here. What is lacking is a falsification of my falsification. Two discrepant behaviors such as heat flow and acoustic propagation cannot both be described as 'vibrating atoms' without explaining the discrepancy, which one would think in all of those texts that have been written someone would have done. It can be said that the modern theory has already gone extradimensional and has swept that bit under the rug, for they have posed multiple freedoms within one domain. I guess I could go on and on with the criticism, but mostly it is just bait for someone who is wise enough to step in here and swat down this argument that I am building. The lack thereof is support for this position that I am taking, though it is a weak form of support.

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Re: Heat conduction in solids: Why is it so slow?

Post by chelle » Thu Nov 25, 2010 6:58 pm

Tim_BandTechDotCom wrote:Also enjoyed the acoustic dust experiment, though I suspect the rotation there is a side effect of the transducer.
Don't you think it might be caused by Static Electricity, that goes over into a current due to the frequency pattern, generating an electric motor?

Image

Faraday motor movie: http://www.youtube.com/watch?v=zOdboRYf1hM
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