Superconductivity at room temperature??

[ben m]

When you apply the junction voltage it is easy to prove to yourself that the electric-field on the lower energy side is now less than on the high energy side. Thus as soon as applying the junction voltage the charge-carriers on the low energy side loses polarization energy relative to the charge carriers on the high energy side. And as I proved on my website this loss is qV.

This sounds very strongly like you have E (electric field strength) confused with V (voltage). Why the heck should the electric field strength be larger in a region where the voltage is large?

It's like a geographer confusing dy/dx (slope) with height and saying "Valleys always have less slope than mountaintops".

 

[johanfprins]

Post #516 outlines that calculation. Your goldfish can fill in the details.

I am really tired of clowning around with your inane posts: How about doing a course in physics at reputable Engineering Faculty: Avoid Physics Departments at all costs unless you are interested in the paranormal claims that a charge-carrier, like an electron, can be accelerated by an electric-field without emitting EM radiation. This is not possible ever.

 

[johanfprins]

Baloney. I just gave you the inputs---the positions, velocities, and accelerations of all the source charges. There are no possible "boundary conditions" that will turn this from a nonradiator into a radiator.

And you gave the solution as you see it. I do not know who you are and if you are really competent when it comes to Maxwell's equations. I suspect that you are not since you ignored simple special relativity when you outlined your rope thought experiment.

Just in case Maxwell's Equations are wrong, right?

No. just in case you are wrong; which seems to me highly likely. If your arguments were relevant to our discussion on whether charge-carriers are being accelerated or not accelerated within a superconductor, I would have spent the time to do the calculations; but even if I then did get the same solution that you say is the solution, I will still check it experimentally like any real scientist who really understand physics, will do. One can derive many solutions from correct differential equations which are physics-nonsense; especially if one is willing to ignore boundary conditions; as you have admitted that you do.

Sorry, Johan. I have gone through this entire thread without insulting you, but your time has now come.

I am not saying you are one, but it is the characteristic of a psychopath not to understand when he/she insults other people.

[*]Having an alternate theory of superconductivity did not make you a crackpot.
[*]Thinking BCS theory is incorrect does not make you a crackpot.
[*]Thinking that you've found a weird superconducting band in a void between electrodes does not make you a crackpot.

Thanks, you surprise me that you can sometimes think for yourself.

[*]Making the (still-extant) energy-conservation mistake brings you pretty close to being a crackpot.

I have made such a mistake initially, and admitted it since I am no a psychopath, but I have corrected it in detail and there is now no (still-extant) violation of energy-conservation at all.

[*]However: saying that you will not accept Maxwell's Equations solutions as counterexamples to your blanket statement about Maxwell's Equations, even though your E&M is "rusty" ... that makes you a crackpot.

I have not said anywhere that Maxwell's equations are wrong or that I do not accept them, but I know that one can derive wrong solutions from correct differential equations, and your physics-expertise has not impressed me so much that I will accept your solutions without skepticism. Furthermore, no real physicist will claim that any solution he derived is correct without experimental verification. In addition, even if you are correct, the "counterexamples" have nothing to do with individual charge-carriers being accelerated by an applied electric-field.

You've fixed an idea about E&M in your head, and shut off all possible avenues for questioning it.

This is a blatant lie and false accusation.

That's the only insult you'll find from me.

Look at your previous postings and you will see that this is also a lie: Or are you just incapable to see yourself?

If you put journal-referees through the same nonsense you pulled on this thread, I'm not surprised they've rejected your papers, and (I hypothesize with a favorable prior probability) they were correct to do so.

Oh my but you know "everything"! You should have been God; not just a mere silly mortal who knows so little about physics that you cowardly hide behind anonymity!

 

[johanfprins]

First off, claiming it's quantum mechanical doesn't help. Quantum mechanics still has acceleration defined as <a> = d²<x>/dt², and that's still nonzero here.

Yes when Ehrenfest's conditions apply so that you have a force defined by a gradient in you applied voltage: I state that one does not have such a gradient within a superconductor. Neither have you given any experimental proof that there is such a gradient!

Although I agree that one cannot measure "zero voltage"; all the experimental results are self-consistent with there being not such a gradient within a superconductor. And the definitions of superconduction within text books are all commensurate with their not being such a gradient. And we know that if there is such a gradient, and the charge-carriers do not scatter, as in the case of a vacuum diode, you do not have superconduction. In addition, in the latter case the accelerating charge-carriers emit EM since they are accelerating. Thus all the evidence are compelling that the charge-carriers within a superconductor must move without acceleration. But you know better since "classical" Newtonian mechanics must, according to you, apply.

And second, by Ehrenfest's theorem, <a> = <-dV/dx>/m. So if you've got a potential barrier, you've got a gradient to your potential (a field, if you like), you've got the quantum mechanical analogue to a force, and you've got a quantum mechanical acceleration.

Do you accept that what is called "tunneling" , no matter how it actually occurs, does happen? Please answer: YES or NO. Do you now maintain that this is caused by Ehrenfest's theorem which accelerates the charge-carrier first against the gradient of the potential barrier, and then with the gradient on the other side of the barrier? Please answer YES or NO. If your answer is NO, where does acceleration come into the equation when "tunneling" occurs?

I already told you: hexagonal lattices have the highest packing fraction.

I have not seen this and apologise if I have missed it.

Vortices repel, so they minimize their energy by adopting a high packing fraction.

I agree that this could be the only reason and should not have slipped up on this.

The idea that it's due to hexagonally arranged orbitals is nonsense,

No it is not just nonsense since the stationary orbitals are formed by harmonic standing waves trapped by induced positive charges. This is also the reason why in most metals (note not all metals) one has a isotope effect. The orbitals and their induced charges can relocate under the action of Coulomb forces between them, and you then find that the orbitals trapping a flux quantum form a hexagonal ring. Nonetheless, even through the latter is a fact, I concede that close-packing could be a sufficient reason for causing the hexagonal arrangement.

Well, no. It's not possible quantum mechanically, you have only declared it to be so.

So you dispute that an electron can change position by what is called "tunneling" in the literature?

And you have even done so without addressing what acceleration even is quantum mechanically.

And you state unequivocally that "tunneling" can only happen when Ehrenfest's law applies? Well be my guest and think what you want, but time will prove that you are wrong. I just hope that when this happens, and you are still alive, you will have the decency to come clean and not disappear behind a screen of anonymity.

I have told you what it is. You have not demonstrated or even suggested that the quantity I defined is nonzero.

Why should I? When Ehrenfest's law applies there is obviously acceleration, but it does not apply to the charge-carriers within a superconductor since these charge-carriers do not radiate any EM. That they must radiate when they are accelerated is proved by Josephson tunneling through an insulator with a voltage across it. When these same charge-carriers are now accelerated (while moving through the junction) they do emit EM. This is incontrovertible proof that they are not accelerating when they move through the superconductor itself.

First, there's nothing wrong with producing kinetic energy in a superconductor with an applied voltage, and second, if the resultant acceleration is perpendicular to the direction of motion (as in the case of a persistent circular current), then no, kinetic energy is NOT generated.

Yes you are correct, but the charge-carriers will emit radiation as they do when they accelerate through a Josephson junction with a voltage across it!

Of course it's not superconduction, there's no Meissner effect.

Let's leave for the time being the Meissner effect aside since it is not understood by the main stream crackpots at all. Let us just for the time being concentrate on you false claim that charge-carriers do accelerate when they transport a current through a superconductor.

And second, you're wrong, there is scattering. Electrons in a vacuum diode can still scatter off each other.

That is not correct: They only repel each other laterally: That is not scattering and dissipating kinetic energy.

No. That is not what happens with a superconducting magnet. The required voltage is not the result of charge injection, but is the result of the inductance of the superconductor.And by the way, every conductor has inductance. It's impossible to not have inductance, because the electron's non-zero mass creates inductance.

I have not disputed the fact anywhere that a superconductor has an induced magnetic field around it: What I do dispute is the stupid idea that this same magnetic field bootstraps an applied voltage within the superconductor: This is utter nonsense! If this could be the case, one would be able to lift oneself into the air by pulling on your bootstraps.

But there IS an applied voltage when you're changing the current in a superconducting magnet, or in fact ANY superconductor.

I have been talking all along about equilibrium conditions. Obviously when you change the EMF around the circuit containing a superconducting element, there will be a transient voltage within the superconductor which will fade away to zero as soon as equilibrium with a higher (or lower) current has been established.

You're trying to draw some artificial boundary between the physics of AC and DC conditions, when no such sharp distinction exists.

It does in a superconductor since an applied DC voltage is cancelled by polarization of the localized charge-carriers. When the voltage changes, this polarization changes, and when you apply an alternating voltage, the dipoles will vibrate and generate EM-radiation when they vibrate in phase with the voltage. You see; there is a hell-of-a-difference.

Furthermore, if you want to talk about DC only, then you are rather automatically NOT talking about the general case, but only a very specific case, so you cannot make absolute declarations of any sort based only on what happens for DC.

I have not made "absolute" declarations: It was clear from the start that we are talking about movement of charge-carriers during the flow of a DC current. It has been people like you who wanted to bring in other boundary conditions all the time. You cannot really be so stupid that you do not realize this? Can you really be?

It's never been described before because it's simply not true. The idea that charges can start moving without accelerating makes no sense, and quantum mechanics cannot and will not rescue this nonsensical idea.

If you became stuck in the 17th century, it will not make sense to you. But during the 20th century new momentous discoveries have been made, which, although wrongly interpreted as paranormal behavior, do make movement of electrons without acceleration possible.

WE have lightning again. So goodbye for now

 

[W.D.Clinger]

Post #516 outlines that calculation. Your goldfish can fill in the details.

I am really tired of clowning around with your inane posts: How about doing a course in physics at reputable Engineering Faculty: Avoid Physics Departments at all costs unless you are interested in the paranormal claims that a charge-carrier, like an electron, can be accelerated by an electric-field without emitting EM radiation. This is not possible ever.

You bring up one interesting point: I have never taken a course in engineering physics or physics for poets. All of the physics courses I have taken were restricted to physics and math majors, with the usual "or permission of the instructor" loophole.

Whether you continue to clown around is up to you. I note, however, that you first mentioned your goldfish in a response to sol invictus.

As for your phrase in bold face, allow me to point out once again that you yourself had acknowledged its irrelevance when you characterized Ziggurat's example, in which the acceleration is not caused by an electric field, as "nonsense":

Ziggurat described a solution to Maxwell's equations in which accelerating charges do not emit EM-radiation.

He described something that is not possible except when doing paranormal physics. He should do the derivation fully and then he will find that he is talking nonsense.

When I took your admonition seriously by outlining the full derivation in Post #516, you simply dismissed the very derivation you had suggested.

You also challenged me to debate Maxwell's equations with your goldfish.

If I have to answer this question, I will have to solve Maxwell's equations for it, since I am only willing to agree or disagree after having done the correct mathematics. Since my electrodynamics is rusty, and I do not want to tackle Jackson again I am not going to waste my time on it.

I guess that explains why you wanted me to debate your goldfish instead of you.

Furthermore, even if one can derive a solution from Maxwell's equations, it might be based on wrong inputs and boundary conditions. One must then check it experimentally; and since none of you have done so, I will be stupid to agree to something which has not been experimentally verified.

As ben m pointed out, your "wrong inputs and boundary conditions" was irrelevant technobabble. I will point out that you did not hesitate to characterize Ziggurat's example as "paranormal physics" and a violation of Maxwell's equations before you had done either the math or the experiment.

As several of us have explained, straightforward application of Coulomb's Law and the Biot-Savart Law to Ziggurat's example yields a radiation-free solution of Maxwell's equations in which charges are accelerating.

You have said several times that no such solution is possible. You are now pretending your false claim was limited to situations in which the acceleration is caused by an electric field, but you knew at the time that Ziggurat's acceleration was mechanical and you still dismissed it as "nonsense", as "paranormal physics". You were wrong.

Anyone can make a mistake, but conversation becomes quite tedious when, instead of acknowledging your mistakes, you deny your own words or attack the knowledge of those who point out your mistakes.

 

[johanfprins]

I can understand how Johan could have a mental image of a quantum tunneling event without velocities or accelerations involved. First you picture the particle sitting still in state A, then you picture the particle sitting still "bridging" states A and B, then you picture the particle entirely in state B. Sure looks like there was no acceleration, right?

This is the paranormal picture that is in your head that the "particle bridges" states A and B. Don't put words in my mouth or think that you are God who knows what I am thinking. You are arrogant and despicable by creating a straw man which you can then attack with nonsense arguments.

One has localized wave-orbitals which are formed by the superposition of all the valence electron waves which bond the atoms together. Wave intensities can change suddenly without acceleration: Have you ever heard of "collapsing waves" And do you know that this requires resonance with the apparatus that collapses it? And do you know that the resonance energy to collapse it is supplied by (delta)E(delta)t=g(hbar), where g depends on the shape size and energy of the wave before it collapses. Do you know that a stationary wave can increase and decrease its energy for short allowed periods of time: This can be deduced from the widths of atomic spectral lines.

A stationary wave can thus temporarily borrow energy and change its position to an equivalent energy position. Now the question arises as to whether such a localized wave has to accelerate in order to move with a speed v to get to the other side of a barrier. You say it must, I say that the experimental evidence is compelling that this transfer, although requiring energy, does not involve "classical acceleration". It is the same as if you are saying that the earth is flat since you can see it must be flat, and I am saying that the evidence indicates that it is spherical. It is the same as you saying that the earth is stationary since for thousands of years this gave the correct information, and you can see that everything moves while the earth is not moving, and I am saying that the evidence is compelling that the earth is moving. We are back at the same impasse that comes when people do not want to even consider that there could be an alternative explanation for what is happening; even though the evidence is overwhelming that there must be an alternative explanation.

No. Once again, vague intuitive pictures are not good enough. Your vague mental picture of classical synchrotron radiation does not agree with Maxwell's Equations.

So synchrotron radiation does not involve acceleration of charges? Well I am always open to new ideas, but I must say that the "counterexamples" that you used are fictitious and physically impossible: Like manufacturing a rope with infinite length that only consists of a single type of charge. Can you not see how crazy this idea is?

Your vague mental picture of this tunneling does not agree with Schrodinger's equation.

The "vague mental picture" that you in your omnipotence sees in my head is clearly not possible. My model flows logically from Schroedinger's equation. Be more specific rather than making such a really vague claim in terms of what you seem to know" that I am thinking.

Zig has (very appropriately) brought up Ehrenfest's Principle, but you've ignored it for no reason at all except that you've already got a mental picture.

Where have I ignored this. When I came to Ziggurat's posts where he brought in Ehrenfest I did not ignore Ehrenfest. Why must you always lie?

An non-Ehrenfest way of thinking about it, if you insist, is to remember that charge is locally conserved. If a particle disappears from location A and reappears in location B, there must be a current flowing.

Not that this argument applies in the present case because the wave does not disappear at one point and reappear at the other point. But as a matter of interest: Can you prove that there can never be non-local transport? Have you heard of quantum-mechanical entanglement? You can have a single, lowest-energy, macro-wave formed by the entanglement of millions of electrons; so that if you inject an electron on one side, another is ejected on the other side without a current flowing between the two positions. BTW I have generated such a phase in my laboratory.

Even in quantum mechanics, electric current is still charge x velocity (just replace the classical velocity with the operator), so the "bridging" state in your mental picture does have a velocity associated with it.

So you are able to read my mind? You must truly be God, or think that you are. I never talked about a "bridging state": There is a speed involved and this speed can be calculated from the Heisenberg relationship without the need to invoke acceleration.

if you didn't want to include that velocity in your mental picture, or didn't want to concentrate on it, that's too bad for you.

If you were not so arrogant to think that you can read my mind and rather first study the model, you will see where the velocity comes from since kinetic energy is included. It would be nice if you would stop to mouth off until you have seen the whole model, instead of making indiscriminate noises. Were you always like this? Your poor mother!

And if you want the A and B states to be stationary, then there is also a velocity associated with them, and it's zero, and lo and behold there has been an acceleration.

Classically yes, but not during quantum-mechanical movement as allowed by resonance

Again, if you didn't want to include acceleration in your vague mental picture, then your vague mental picture is wrong. As I have pointed out again and again, whether you want to believe you are God or not, you are not. You are not able to read "a vague model" in my mind: You want to create a "vague model" in your mind to use as a straw man. I find your attitude despicable. According to you the earth is flat and will remain flat for you; and anybody else saying the opposite must have a "vague mental picture" which you can see since you are the almighty.!

You can't claim that the acceleration is zero, on the grounds that you're able to form a mental picture that ignores it.

where have I done this? It takes my breath away that anybody could be so arrogant as you are without having seen the mathematics which is solidly based on Schroedinger' equation. Like I said, it seems that you are thinking you are God! Sorry to disillusion you my boy: I do not even think that you could be a competent physicist. Show me your citation index!

 

[johanfprins]

I can understand how Johan could have a mental image of a quantum tunneling event without velocities or accelerations involved. First you picture the particle sitting still in state A, then you picture the particle sitting still "bridging" states A and B, then you picture the particle entirely in state B. Sure looks like there was no acceleration, right?

This is the paranormal picture that is in your head that the "particle bridges" states A and B. Don't put words in my mouth or think that you are God who knows what I am thinking. You are arrogant and despicable by creating a straw man which you can then attack with nonsense arguments.

One has localized wave-orbitals which are formed by the superposition of all the valence electron waves which bond the atoms together. Wave intensities can change suddenly without acceleration: Have you ever heard of "collapsing waves" And do you know that this requires resonance with the apparatus that collapses it? And do you know that the resonance energy to collapse it is supplied by (delta)E(delta)t=g(hbar), where g depends on the shape size and energy of the wave before it collapses. Do you know that a stationary wave can increase and decrease its energy for short allowed periods of time: This can be deduced from the widths of atomic spectral lines.

A stationary wave can thus temporarily borrow energy and change its position to an equivalent energy position. Now the question arises as to whether such a localized wave has to accelerate in order to move with a speed v to get to the other side of a barrier. You say it must, I say that the experimental evidence is compelling that this transfer, although requiring energy, does not involve "classical acceleration". It is the same as if you are saying that the earth is flat since you can see it must be flat, and I am saying that the evidence indicates that it is spherical. It is the same as you saying that the earth is stationary since for thousands of years this gave the correct information, and you can see that everything moves while the earth is not moving, and I am saying that the evidence is compelling that the earth is moving. We are back at the same impasse that comes when people do not want to even consider that there could be an alternative explanation for what is happening; even though the evidence is overwhelming that there must be an alternative explanation.

No. Once again, vague intuitive pictures are not good enough. Your vague mental picture of classical synchrotron radiation does not agree with Maxwell's Equations.

So synchrotron radiation does not involve acceleration of charges? Well I am always open to new ideas, but I must say that the "counterexamples" that you used are fictitious and physically impossible: Like manufacturing a rope with infinite length that only consists of a single type of charge. Can you not see how crazy this idea is?

Your vague mental picture of this tunneling does not agree with Schrodinger's equation.

The "vague mental picture" that you in your omnipotence sees in my head is clearly not possible. My model flows logically from Schroedinger's equation. Be more specific rather than making such a really vague claim in terms of what you seem to know" that I am thinking.

Zig has (very appropriately) brought up Ehrenfest's Principle, but you've ignored it for no reason at all except that you've already got a mental picture.

Where have I ignored this. When I came to Ziggurat's posts where he brought in Ehrenfest I did not ignore Ehrenfest. Why must you always lie?

An non-Ehrenfest way of thinking about it, if you insist, is to remember that charge is locally conserved. If a particle disappears from location A and reappears in location B, there must be a current flowing.

Not that this argument applies in the present case because the wave does not disappear at one point and reappear at the other point. But as a matter of interest: Can you prove that there can never be non-local transport? Have you heard of quantum-mechanical entanglement? You can have a single, lowest-energy, macro-wave formed by the entanglement of millions of electrons; so that if you inject an electron on one side, another is ejected on the other side without a current flowing between the two positions. BTW I have generated such a phase in my laboratory.

Even in quantum mechanics, electric current is still charge x velocity (just replace the classical velocity with the operator), so the "bridging" state in your mental picture does have a velocity associated with it.

So you are able to read my mind? You must truly be God, or think that you are. I never talked about a "bridging state": There is a speed involved and this speed can be calculated from the Heisenberg relationship without the need to invoke acceleration.

if you didn't want to include that velocity in your mental picture, or didn't want to concentrate on it, that's too bad for you.

If you were not so arrogant to think that you can read my mind and rather first study the model, you will see where the velocity comes from since kinetic energy is included. It would be nice if you would stop to mouth off until you have seen the whole model, instead of making indiscriminate noises. Were you always like this? Your poor mother!

And if you want the A and B states to be stationary, then there is also a velocity associated with them, and it's zero, and lo and behold there has been an acceleration.

Classically yes, but not during quantum-mechanical movement as allowed by resonance

Again, if you didn't want to include acceleration in your vague mental picture, then your vague mental picture is wrong.

As I have pointed out again and again, whether you want to believe you are God or not, you are not. You are not able to read "a vague model" in my mind: You want to create a "vague model" in your mind to use as a straw man. I find your attitude despicable. According to you the earth is flat and will remain flat for you; and anybody else saying the opposite must have a "vague mental picture" which you can see since you are the almighty.!

You can't claim that the acceleration is zero, on the grounds that you're able to form a mental picture that ignores it.

where have I done this? It takes my breath away that anybody could be so arrogant as you are without having seen the mathematics which is solidly based on Schroedinger' equation. Like I said, it seems that you are thinking you are God! Sorry to disillusion you my boy: I do not even think that you could be a competent physicist. Show me your citation index!

 

[johanfprins]

Thanks Johan, that clears up in my mind where the radiation comes from within a Josephson junction.

Thanks Skwinty, it is always a pleasure to communicate with an engineer who has common sense.

I think that people take issue with the fact that you are using the statement "It radiates as any accelerated charge-carriers must." because it is apparent that a stationary charge carrier on earth does not radiate even though it is under gravitational acceleration.

I am sorry if this was the impression since I have all along been arguing about charge-carriers being accelerated by an electric-field within a superconductor. I did no think that people could be so stupid to take things out of context when they full well know that I was not in any way talking about any other type of acceleration like mechanical and gravitational.

On this forum, one needs to be precise otherwise all the exceptions to the "rule" will be laid on the table.

It should not be so since a "full mind only needs half a word". But thanks for warning me that on this forum I am dealing mostly with half-wits who need baby-talk explanations.

The fact that the junction is the source of radiation, implies, that we are back to classical again as the insulator is not superconducting, merely the region of electric field acceleration, hence no radiation in the S part of the SIS sandwich.

Correct, and it also proves that if these charge-carriers accelerate they WILL emit radiation: And since they move through the superconductor WITHOUT emitting radiation, they must be moving without being accelerated. Whether you want to argue that it is not possible, is irrelevant, since this is the incontrovertible experimental fact; just like the fact that the earth is not flat and not stationary.

Bye for now

 

[sol invictus]

Johan,

I no longer see the point in responding to the details of your posts. You are making basic mistakes on the most simple aspects of physics - the relationship between potential and kinetic energy, acceleration, and velocity - but you've clearly long since made up your mind that you are right and everyone else is wrong, and nothing I can say will convince you otherwise.

I suggest you read this paper: "Unskilled and unaware of it: How difficulties in recognizing one's own incompetence lead to inflated self-assessments", as it perfectly describes you.

 

[Skwinty]

Hi Sol,
Your link is broken and only returns

We are sorry !

This URL does not match any resource in our repository.

 

[Skwinty]

Please explain to me why there is such discord amongst all you clever people.

The thread is about superconductivity at room temperature, not superconductivity that requires extreme low temperatures.

I am assuming here that room temperature superconductivity is included in the realm of high temperature superconductivity as described below.

I will bold the relevant parts relating to my confusion which is generated by the discord.

"Yet experiments led by SIMES researchers Makoto Hashimoto and Rui-Hua to suggest that the electron-pairing model does not describe what happens in the newer high-temperature superconductors.
"In 2006, our group published a paper suggesting that there are two types of distinct energy gaps," He said. "This more recent work provides a conclusive argument that there are two different mechanisms involved here."
The researchers trained the X-ray beam of SLAC's Stanford Synchrotron Radiation Lightsource on a high-temperature superconductor to reveal the material's electronic structure and explore the nature of the pseudogap. They were on a hunt for evidence of the electron pairing seen in conventional superconductors, in the form of what's called "electron-hole symmetry"; if it were present in the pseudogap, then the road to designing even higher temperature superconductors would be to make the pairs dance together instead of resting dormant.
But that's not what the researchers found; under the bright X-ray beam, the high-temperature superconductor showed a clear lack of the telltale symmetry—and thus of electron pairing. This suggests that the electron pairs were not lying dormant; they were simply not there.
The researchers posit that the electrons do not pair in this temperature range and instead travel in a wave; what they observed at SSRL were crests and troughs of electron density. The electrons' tendency to travel in a density wave may compete with their efforts to pair, suggesting that scientists will need a different approach in order to create a room-temperature superconductor.
"This is a very difficult problem, but an important one to solve," said Hashimoto. "We don't yet know the details of the density wave, but by extending our studies to different materials we are now seeking to understand it."


http://www.physorg.com/news189798601.html

ETA: link to publication http://www.nature.com/nphys/journal/v6/n6/abs/nphys1632.html

Now, perhaps a stupid question wrt the extra energy that Johan talks about, does the electron at the crest of the density wave not have more energy than the electron at the trough of the wave?

 

[Ziggurat]

Yes when Ehrenfest's conditions apply so that you have a force defined by a gradient in you applied voltage: I state that one does not have such a gradient within a superconductor. Neither have you given any experimental proof that there is such a gradient!

It doesn't matter what sort of potentials you think you cannot have, you still have a nonzero d²<x>/dt² if the electrons are moving in a circle. You keep trying to claim that they can move in a circle without an acceleration, and I keep telling you that quantum mechanics says you're wrong. d²<x>/dt² is nonzero in such an event.

Although I agree that one cannot measure "zero voltage"; all the experimental results are self-consistent with there being not such a gradient within a superconductor.

Except, of course, for all the experimental evidence demonstrating a changing current in a superconductor.

Thus all the evidence are compelling that the charge-carriers within a superconductor must move without acceleration. But you know better since "classical" Newtonian mechanics must, according to you, apply.

No, according to Ehrenfest's theorem, expectation values must obey Newtonian mechanics. Not under certain conditions, but always. Otherwise quantum mechanics is wrong, and you're not claiming it is.

Do you accept that what is called "tunneling" , no matter how it actually occurs, does happen? Please answer: YES or NO.

Yes.

Do you now maintain that this is caused by Ehrenfest's theorem which accelerates the charge-carrier first against the gradient of the potential barrier, and then with the gradient on the other side of the barrier? Please answer YES or NO.

Tunneling happens in agreement with Ehrenfest's theorem, yes.

Nonetheless, even through the latter is a fact, I concede that close-packing could be a sufficient reason for causing the hexagonal arrangement.

OK, that's some progress we've made.

So you dispute that an electron can change position by what is called "tunneling" in the literature?

Nope, I agree that tunneling can and does occur.

And you state unequivocally that "tunneling" can only happen when Ehrenfest's law applies?

I'm claiming Ehrenfest's theorem always applies to quantum mechanics, including tunneling scenarios. And it's a theorem, not a law, because it is a mathematical consequence of the theory. Any breakdown in Ehrenfest's theorem is synonymous with a breakdown in quantum mechanics. Which could happen, but that's not what you're proposing.

Why should I? When Ehrenfest's law applies there is obviously acceleration, but it does not apply to the charge-carriers within a superconductor since these charge-carriers do not radiate any EM.

Nothing about Ehrenfest's theorem provides for any such exception.

That they must radiate when they are accelerated is proved by Josephson tunneling through an insulator with a voltage across it.

Well, no. One example of accelerating charges that radiate logically cannot prove that all accelerating charges radiate. But one example where accelerating charges do not radiate will disprove that. And I, and others, have given you such examples.

Let's leave for the time being the Meissner effect aside since it is not understood by the main stream crackpots at all.

The effect is easily understood (even at the time), even if the cause is not. Zero resistance in the absence of a Meissner effect is not superconductivity, it is perfect conductivity.

That is not correct: They only repel each other laterally: That is not scattering and dissipating kinetic energy.

You're wrong. They interact (and thus scatter) along the direction of current motion as well.

Furthermore, scattering doesn't have to dissipate kinetic energy. Coherent scattering (as in a diffraction experiment) involves no change in kinetic energy.

I have not disputed the fact anywhere that a superconductor has an induced magnetic field around it: What I do dispute is the stupid idea that this same magnetic field bootstraps an applied voltage within the superconductor: This is utter nonsense! If this could be the case, one would be able to lift oneself into the air by pulling on your bootstraps.

You claim it's nonsense, but the results predict exactly what occurs. The induced voltage accelerates electrons, creating a current that counter-acts the applied field. As the applied field is canceled, the voltage drops to zero, and no more acceleration. The current is then persistent, and does not continue to change.

I have been talking all along about equilibrium conditions.

Because you think that gets you out of having to explain what contradicts your theory. But it won't work. The laws of physics aren't different under equilibrium, I've given you examples of equilibrium conditions which do what you claim could not be done, and from the point of view of an individual electron, even your equilibrium conditions are not, in fact, in equilibrium at all.

Obviously when you change the EMF around the circuit containing a superconducting element, there will be a transient voltage within the superconductor

FINALLY!

Which means that voltages, AND electric fields, are not prohibited in a superconductor. And neither are accelerations.

If you became stuck in the 17th century, it will not make sense to you. But during the 20th century new momentous discoveries have been made, which, although wrongly interpreted as paranormal behavior, do make movement of electrons without acceleration possible.

You keep saying this, and never backing it up. How do you get an electron to move in a circle with nonzero d²<x>/dt²?

 

[johanfprins]

You are the one saying that charges behave differently when the sources are accelerated by an E-field, versus when they accelerate mechanically.

Another one of your lies! How the hell can a person like you with such a lack of decency live with yourself? I have never brought up the topic of electric-field acceleration compared to mechanical acceleration. It has been you, and other people with the same despicable mentality that you have, who raised this as a red herring.

You furthermore say that you wouldn't believe that a spinning disk is nonradiating, without direct experimental evidence

Well I have never done such an experiment and when a person like you claim that it is so, one would be a fool not to be skeptical; even though the argument is irrelevant to the topic being discussed.

implying that merely solving Maxwell's Equations is not enough.

A person who thinks that "merely solving differential equations" is enough, is not a scientist a-----e. It has always been the rule that you must confirm any calculation and derivation by experimental measurements. A person who believes otherwise should be banned from doing physics or any other science for that matter.

Furthermore I told you that you are ignoring boundary conditions. To do the calculation one should know how the charges are attached to the disc. Have you, for example, used an acrylic polymer? Then the charges form part of a dielectric: Only a complete idiot will solve Maxwell's equations without taking this into account. Any method of attaching charge to a solid body involves the formation of polarization fields; and only a complete moron will solve the equations without taking such fields into account.

v is velocity (vector)
a is acceleration (vector)
. is the dot product.Whenever v.a = 0 there is no change in speed (|v| or magnitude v) and no increase in kinetic energy.

My you are clever: We are arguing about the emission of radiation when charge-carriers accelerate under the action of an electric-field: Even if the acceleration and speed are perpendicular to each other the charge-carrier will radiate. They already knew this nearly 100 years ago after Rutherford claimed that electrons can circle a nucleus. They cannot do so ever without radiating EM and spiraling into the nucleus.

Acceleration does not mean a change in speed or kinetic energy. Acceleration means a change in any aspect of the velocity vector.

And you insult me by wanting to claim that I do not know this.

You would not be able to earn even a B in my freshman mechanics class without understanding this fact.

You should not have been allowed to pass Kindergarten.

 

[johanfprins]

What energy source restores the lost polarization energy when this electron comes around the loop again?

Many years ago there was an Italian with the name of Volta which discovered what they then called a "voltaic pile" . At present we call it "a battery". But with electronics we can even generate voltage differences using a "power" source.

Funnily enough, when a charge carrier is at zero voltage and moves through such a device it increases its potential energy. Quite an amazing discovery I would say. In fact my grandchildren in Kindergarten already know about it. Thank God, I am not in your freshman course! At which University you said you are teaching?

 

[Ziggurat]

Please explain to me why there is such discord amongst all you clever people.

The thread is about superconductivity at room temperature, not superconductivity that requires extreme low temperatures.

I am assuming here that room temperature superconductivity is included in the realm of high temperature superconductivity as described below.

Not according to johan.

Most physicists believe superconductivity occurs because of the formation of Cooper pairs (electrons which bind with each other), thus allowing the charge carriers (the pairs, not individual electrons) to obey Bose statistics instead of Fermi statistics. If Cooper pairs form, then zero resistivity is a natural consequence. The difficulty is that to form these pairs, you need the electrons to attract each other, even though Coulomb repulsion is trying to prevent pair formation.

BCS theory was basically a description of how lattice vibrations could provide a mediated attractive force between electrons that could allow them to form Cooper pairs. For high-Tc materials, this description seems to break down, meaning that some other pairing mechanism is responsible, even though it hasn't been identified. But it's still a pairing mechanism which is believed to be responsible in all cases. And the strength of the pairing mechanism is what determines Tc. The difficulty with room temperature superconductivity is that nobody knows if it's possible to get a pairing mechanism strong enough.

johan, on the other hand, doesn't think that superconductivity of any kind involves Cooper pairs.

 

[Ziggurat]

Many years ago there was an Italian with the name of Volta which discovered what they then called a "voltaic pile"

That gets you an energy QV. But You're claiming an energy 2QV.

You still haven't resolved this energy conservation violation.

 

[ben m]

Many years ago there was an Italian with the name of Volta which discovered what they then called a "voltaic pile" . At present we call it "a battery". But with electronics we can even generate voltage differences using a "power" source.

A voltaic pile or battery delivers 1 qV per electron. The presence of this 1 qV is accounted for by the V difference in the Fermi levels.

You need something to deliver another qV "polarization energy" in addition to the Fermi level change.

 

[johanfprins]

This sounds very strongly like you have E (electric field strength) confused with V (voltage). Why the heck should the electric field strength be larger in a region where the voltage is large?

It's like a geographer confusing dy/dx (slope) with height and saying "Valleys always have less slope than mountaintops".

I first skip Ziggurat's long rambling crackpot arguments to answer this question before I definitely have to sign off.

You see little Ben, the experiment works as follows: You start off with a SIS sandwich over which you apply a voltage V_source, and you then find that a current flows without any voltage V_J across the insulator. Assume that the contact into which the charge-carriers are flowing is grounded, so that we have a reference voltage of zero. You must then conclude (if you know the difference between voltage and electric-field; which I doubt) that the electric-field being cancelled is the same everywhere and therefore the polarization of the superconducting orbitals is the same on both sides of the insulating junction.

Now you place a capacitor parallel to the power source across tye SIS sandwich, and a very remarkable thing happens: Guess what happens my little boy? A voltage V_J appears over the junction, without any change in V_source over SIS. Now if you are able to understand that the slope of the applied voltage is equal to the applied electric-field (maybe I am expecting TOOO much from you; but come back if I have to try and make it simpler for you to understand) , you will have to conclude, if you really try to think hard, that the voltage drop over the grounded part of the SIS sandwich must now be lower than on the other side: An just guess what my little boy, this means that the slope of the cancelled voltage on the grounded side is less than on the other side: AND, this in turn, means that the electric field bing cancelled is less on the grounded side. Remarkable is it not? But if you are not able to understand it; drink your bottle of milkies and go to sleep: Pappa will again explain it to you tomorrow. Sleep well.

Nighty night:

 

[ben m]

Another one of your lies! How the hell can a person like you with such a lack of decency live with yourself? I have never brought up the topic of electric-field acceleration compared to mechanical acceleration.

Au contraire:

Not under the action of an electric-field.

I hope you are not again dishonest. I am talking about charges which are not mechanically bonded but are each accelerated by an electric-field.

I have claimed that if charge carriers are accelerated by an electric field to negotiate a bend, they will radiate ... It is you who conclude that the usual descriptions which demand radiation is suddenly not true since the charges must move like charges bonded to a spinning disc. I say the the usual descriptions demand that there must be radiation when the charge-carriers are being accelerated by an electric-field

However, the latter possibility does not interest me since whether they are correct or incorrect does not pertain to the original argument as to whether charge-carriers move through a superconductor by being accelerated by an electric-field or not.
Disagree with the last sentence: If the charge-carriers move since they are accelerated by an electric-field, you will have the same situation as you have when accelerating electrons from a cathode to an anode. Even if you want to believe that for some "magic paranormal" reason these accelerating electrons do not radiate EM, they are not a superconducting phase.

you claimed that each of them can be accelerated by an electric field without emitting EM.

Whatever, your present hand-waving arguments based on "ensembles" are, they do not change the fact that when these charge-carriers are accelerated by an electric field they WILL radiate EM.

Since the is no difference between electric and non-electric acceleration, then the spinning-disk example is a relevant counterexample to your blanket "acceleration=radiation" claim.

 

[Skwinty]

johan, on the other hand, doesn't think that superconductivity of any kind involves Cooper pairs.

Thanks for the reply Zig.

In all fairness, Johan has written two books.

The Physics Delusion.

Excerpts from this book led me to believe he was a crackpot.

The second book is called "Room Temperature Superconductivity without Cooper Pairs"

I have not read this book and even if I did, I would not qualify to make any judgement on its veracity because it is not my field.

I have been following this thread with the intention of learning something about it, therefore I have always assumed the arguments were about high temperature superconductivity.

Coupled with other papers I have read, it seems clear to me that the mainstream is busy with trying to understand what the mechanisms are that allow this phenomenom to occur.

I suppose only time will tell what the reality of the situation is and in the meantime we are just whistling in the dark.
Lets hope that the mainstream who have the labs and the budget, get to the root of the matter.