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Quote:
Originally posted by J. Arthur God:
[
This may come across as being part of the stodgy old establishment, but it is a fact.

If I have the option of believing that a Nobel Prize winning theory that has been in constant use for decades over a new theory which has been rejected twice by peer review...I will pick the Nobel Prize winning theory.

I'll probably be correct 99.99999% of the time. If I could get odds like that in Vegas, I'd be a rich man.

The burden of proof is on you. I believe you haven't met it. This is at least as valid as your belief that your theory is going to be earth shattering. [/QUOTE]

Why am I not surprised. Those people who are not willing to use scientific sense judge on probabilty. You have now proved without any doubt that you are, and NEVER can be, a scientist. It is not "probabilty" which should lead a scientist, but scientific principles. I have challenged you to explain how BCS models superconduction between two contacts. The burden of the proof is on YOU! Why do you not do so? Because you BELIEVE that BCS MUST be correct; and are incapapble of discussing science logically. Nothing has changed since the time of Galileo!! Talking about Las Vegas; how much are you willing to bet on the BCS model? Put your money where your mouth is! BEING SO SURE OF YOURSELF YOU WILL OF COURSE GIVE ME ODDS OF 99.99999999% Well I will be gracious: $1000 from me for $1000,000 from you! How's that?

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I apologise for the many postings; but I continually got messages of rejection and thus had to try again.

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I apologise for the many postings; but I continually got messages of rejection and thus had to try again.

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I have only now seen the postings og JAG on the previous page: I am not going to even try and answqer all the nonsense JAG has posted, except to ask one question: IF Cooper Pairs are the required charge-carriers for suoperconduction, why do the "high-temperature" superconductors not show an isotope effect. JAG try to act and reason like a scientist; PLEASE.

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You are subtle, but I gather you disagree with my last post.

Yes, people believe that BCS is correct--or is at least a workable theory. Hundreds, if not thousands, of people have used the BCS theory with success.

Do people believe that BCS is the all encompassing theory that explains all there is to say about superconducivity? Nope.

Here's something that shouldn't be news to you. No theory is correct. All of these mathematical constructs are just our way of modelling what nature does. Sometimes they work really well, but they are still just tool. Anyone who completely believes any theory is a true description of reality is a fool. My guess is that Bardeen, Cooper and Schriefer would all agree that their theory is not a complete description of superconductivity.


Look up who made this quote. And, no, I don't think I am in the same league as this gentleman.

"The de Broglie-Schrodinger wave fields were not to be interpreted as a mathematical description of how an event actually takes place in time and space, though, of course, they have reference to such an event. Rather they are a mathematical description of what we can actually know about the system. They serve only to make statistical statements and predictions of the results of all measurements which we can carry out upon the system."

By the way, I have used more than probability. I have used my education, experience and common sense. You asked for people to read and critique your paper. I did so. I notice that you are not addressing my technical concerns with your paper.

You are not Gallieo. Do yourself a favor, drop that line. It really, seriously, honestly, doesn't help your case. Quite the opposite, in fact.

Drop the whole, "the establishment is against new ideas" line as well. Sorry, but the establishment is actually hungry for new ideas. A good one you would have to keep from being stolen.

By the way, probability should definitely lead a scientist. Probability is the basis of statistical mechanics. The same person who made the quote noted above supposedly considered this to be one of the most elegant forms of physics.

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Quote:
Originally posted by Johnny Boy:
I have only now seen the postings og JAG on the previous page: I am not going to even try and answqer all the nonsense JAG has posted, except to ask one question: IF Cooper Pairs are the required charge-carriers for suoperconduction, why do the "high-temperature" superconductors not show an isotope effect. JAG try to act and reason like a scientist; PLEASE.
You have been reading Uncle Al's posts and taking him at his word. This is a dangerous practice.

There is an isotope effect in High-Tc superconductors. It is often lower than expected. Sometimes it is negative. It has been attacked using BCS as a basis. One feature is that the phonons important are only in the CuO sheets. So, changing the isotope of, say, La, doesn't have the effect one would expect from a simple application of BCS.

That said, scientists start by doing a literature search.

As an expert in superconductivity, I am sure you have read this paper:

Interplay of electron-phonon interaction and strong correlations: the possible way to high-temperature superconductivity
by M.L. Kulic in Physics Letters (338, pg 1-264 (2000).

Here are some quotes from the abstract.

"However, there are experimental evidences that the electron-phonon (E-P) interaction together with strong electronic correlations plays a decisive role in the formation of the normal state and superconductivity."


"The tunneling experiments show also that almost all phonons contribute to the pairing interaction and the E-P interaction is sufficiently large to produce T-c similar to 100 K. The strong E-P interaction is due to (a) the layered and almost ionic-metallic structure of HTS oxides; (b) the almost two-dimensional motion of conduction carriers, which give rise to large contribution of the Madelung energy in the E-P interaction, especially for axial phonons. "

Sounds like a lot of evidence is out there for electron-phonon interaction in High-Tc superconductors. Does your theory match the tunneling spectroscopy data?

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You've the patience of a saint JAG.

After the way he treated you I wouldn't respond to him if he was up to his neck in quicksand.

People that rail against "the establishment" may or may not have a point. But they are always setting themselves up for failure.


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Quote:
Originally posted by DA Morgan:
You've the patience of a saint JAG.

After the way he treated you I wouldn't respond to him if he was up to his neck in quicksand.

People that rail against "the establishment" may or may not have a point. But they are always setting themselves up for failure.
Actually, I was not pleased with statements in the previous thread. I asked some questions, and JB made responses. I didn't agree with them, but didn't have time to make a post. He implied that my silence somehow implied that he had convinced me. I want to be very clear this time.

I must say that I find his recent arguments odd.

His theory has nothing to say on the isotope effect at all. He has suggested some handwaving arguments in this forum.

BCS explains the isotope effect well in standard materials but not so well in High-Tc.

Therefore, we are to conclude that BCS is wrong and he is correct.

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I was taught that anyone proposing a new theory MUST explain how what they write is consistent with the current art and further explain how it may differ from current art.

To have not discussed some of the issues you've brought up is a major shortcoming.


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JAG: "There is an isotope effect in High-Tc superconductors. It is often lower than expected. Sometimes it is negative. It has been attacked using BCS as a basis. One feature is that the phonons important are only in the CuO sheets. So, changing the isotope of, say, La, doesn't have the effect one would expect from a simple application of BCS."

I am aware of this and if you go back to what I have posted on the isotope effect you will see that I have said that the coupling with phonons is weaker in the CuO ceramics because the charge-carriers are formed between the layers where the electrons are bonded together by the standard exchange force (similar to the covalent bond). The phonons are within the layers. This does not totally exclude any interaction between the phonons and the charge carriers, but it will be much weaker than in the low temperature metals where both the charge carriers and phonons are internal to the material.

JAG: "That said, scientists start by doing a literature search."

I have and I am still doing so. I must admit that I am still catching up. I have been helped by buying a pair of hellish expensive books from Cambridge U in which the work on high temperature superconductors have been summarised. I am aware of the tunnelling experiments and they are commensurate with my model. Unfortunately I do not have access to STEM; however, I have other data that are commensurate with the tunnelling data. Unfortunately I have not yet obtained the go-ahead from my patent attorneys to publish. Hopefully I will be able to place it on arxive before the end of this year. BTW if you go to my article on my model which I have posted on arxive you will find that I have tried to accomodate your comments which I considered as useful; I also deal with the isotope effect.

DA: "After the way he treated you I wouldn't respond to him if he was up to his neck in quicksand."

If you share this feeling JAG, then I apologise because it has not been my intention to treat you badly.

JAG: " must say that I find his recent arguments odd.

His theory has nothing to say on the isotope effect at all. He has suggested some handwaving arguments in this forum.

BCS explains the isotope effect well in standard materials but not so well in High-Tc."

AS I have just now posted, the isotope effect is discussed in the version of my manuscript on arxive. My model explains the isotope effect well in all materials. If you go back to Wigner's treatment which predicts the formation of a Wigner crystal, you will find that the energy of the electron orbitals that form will depend on the isotope mass. Furthermore, it also gives a reason why superconduction do not accur in good conductors like gold and copper. In these materials the mean-field theory applies well. A Wigner crystal manifests when the mean-field approach breaks down. This is what one expects for a superconductor and this is also borne out by the tunneling experiments you have quoted above. This is another argument against BCS: it is a mean-field theory (patched together with fudge factors called "coherence lengths"); and thus, most probably, a very crude approximation of what the mechanism really is.

DA: "I was taught that anyone proposing a new theory MUST explain how what they write is consistent with the current art and further explain how it may differ from current art.

To have not discussed some of the issues you've brought up is a major shortcoming."

What you say I MUST do, is exactly what I have done in my manuscript; and I have addressed the issues raised by JAG; I even made modifications in my manuscript which I finally posted on arxive.

My whole article has a basic thrust which both JAG and DA ignore completely (why?): this is the following:

BCS cannot model a superconducting current that flows between two contacts; because it has to explain the following; which it cannot:

1. How the charge carriers can increase their velocities without manifesting kinetic energy: if they manifest kinetic energy, they will scatter within the contact they are moving into and this will register as a resistance (just as in the case for electrons in a vacuum diode).

2. In order for the charge-carriers not to accelerate, which must manifest kinetic energy when it occurs, the superconducting phase must "expel" any applied electric field: i.e. the material MUST be a perfect dielectric. BCS does not give a mechanism for this.

My model explains both these requirements and it fits experimental results that have been measured for ALL types of superconductors discovered to date. This is exactly where my model differs from "current art" which cannot explain high Tc superconductors. Thus to accuse me of what you accuse me of above is untrue and petulant.

In addition to the fact that the BCS model cannot explain SC between two contacts (and thus not any superconduction); it is a very complicated model. My model is simpler and can model everything BCS can supposedly model and more. What does Occam's razor tell you?

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I have only now seen this posting on the previous page:

Quote:
Originally posted by J. Arthur God:


Yes, people believe that BCS is correct--or is at least a workable theory. Hundreds, if not thousands, of people have used the BCS theory with success.

Do people believe that BCS is the all encompassing theory that explains all there is to say about superconducivity? Nope.

Here's something that shouldn't be news to you. No theory is correct. All of these mathematical constructs are just our way of modelling what nature does. Sometimes they work really well, but they are still just tool. Anyone who completely believes any theory is a true description of reality is a fool. My guess is that Bardeen, Cooper and Schriefer would all agree that their theory is not a complete description of superconductivity.
I am insulted by this posting; You do not need to lecture me on the limitations of physics: I probably am way ahead of you when it comes to this topic. Therefore I am always open-minded when new ideas are mooted. Why are you not? It seems to me that you do not practise what you preach.

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And further:

Quote:
Originally posted by J. Arthur God:
"The de Broglie-Schrodinger wave fields were not to be interpreted as a mathematical description of how an event actually takes place in time and space, though, of course, they have reference to such an event. Rather they are a mathematical description of what we can actually know about the system. They serve only to make statistical statements and predictions of the results of all measurements which we can carry out upon the system."

By the way, I have used more than probability. I have used my education, experience and common sense. You asked for people to read and critique your paper. I did so. I notice that you are not addressing my technical concerns with your paper.

I am glad you have brought up that quote; because it lies at the root of the problems we have had in modern physics for over 80 years. I have come to the conclusion that this is an incorrect interpretation of the statistical nature of some quantum mechanical processes like radio-active decay and wave-collapse. The statistics of these processes does not relate to the wave-function representing a probability distribution; but to Heisenberg's Uncerainty Relationship for energy and time; as well as the ability of the wave to morph when the boundary conditions change. I have posted another manuscript on arxive which in my opinion addresses these aspects.

What you should use when reading a manuscript is your ability to do science. In your case it is clear to me that your "education, experience and common sense" is not enough. Having written this, I want to confirm that this is not meant as an insult to you. In fact I am grateful that you did put in the effort and did come back with arguments. This is how a scientific critique must be handled (DA should take note). Thus I want to thank you very much; however, I do not know which technical aspects you claim that I have not addressed. From my viewpoint it is you who are not addressing the technical and scientific aspects in my manuscript. See two postings up.

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Quote:
Originally posted by Johnny Boy:
1. How the charge carriers can increase their velocities without manifesting kinetic energy: if they manifest kinetic energy, they will scatter within the contact they are moving into and this will register as a resistance (just as in the case for electrons in a vacuum diode).
You keep bringing this up, but it makes no sense. Perhaps to you it does, but if that is the case, you are not communicating it well.

An electron moves from a superconductor to a normal conductor contact. It scatters, creating resistance--IN THE NORMAL METAL. Wow, there is resistance in a normal metal in contact with a superconductor. Let's throw BCS out the door!

Quote:


2. In order for the charge-carriers not to accelerate, which must manifest kinetic energy when it occurs, the superconducting phase must "expel" any applied electric field: i.e. the material MUST be a perfect dielectric. BCS does not give a mechanism for this.
No, charge carriers do accelerate in superconductors. One can even measure it.

http://www.ncbi.nlm.nih.gov/entrez/query...p;dopt=Abstract

You want to expell all electric field? You need a perfect conductor. Read part 2 of Halliday and Resnick. There is a section on capacitors.

Quote:

My model explains both these requirements and it fits experimental results that have been measured for ALL types of superconductors discovered to date. This is exactly where my model differs from "current art" which cannot explain high Tc superconductors. Thus to accuse me of what you accuse me of above is untrue and petulant.

"...and it fits experimental results that have been measured for ALL types of superconductors discovered to date"

I'm sorry, where did your model actually fit the isotope effect in, say, tin? I don't recall that figure in your paper. I.e. where is a quantitative analysis of the isotope effect for a simple superconductor? You don't have it, so don't make this claim.

Quote:

In addition to the fact that the BCS model cannot explain SC between two contacts (and thus not any superconduction); it is a very complicated model. My model is simpler and can model everything BCS can supposedly model and more. What does Occam's razor tell you?
Your model is high school algebra applied to unphysical assumptions. Two experts in the field have told you it is incorrect. Occam's razor tells me that the easiest decision was to take their advice and not read your paper--i.e. you are wrong. Not being a lazy scientist, I chose to read your paper.

Have fun with Occam's razor in your work.

Here's a trick for those of us second rate scientists who measure resistance of materials on a daily basis. Use a 4-point probe. You are making grandiose claims based on the fact that there is a resistance in your 2-point model. PRL would have rejected Bednorz and Mueller with their 4-point measurements. You can imagine that 2-point measurements wouldn't have gotten them into any journal.

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OK, I have answered your questions. Yes, I can predict the future and tell that you disagree with my statements. Oh well, I am crushed.

Now, back to one (of many) problems in your theory that you never want to address.

You state that the number denisty of superconducting electrons goes down with temperature. Thus, the average distance between conduction electrons increases.

From this, you make the leap that the distance between available sites increases.

Occam's razor (and most of solid state physics) would have your first explore that the site occupancy decreases with temperature. I.e. the distance between allowed sites for electrons remains nominally the same, but the probability (ooh that bad word) of a charge carrier being on a site goes down.

So, the distance a carrier would have to tunnel in your model would remain the same. This would negate much of your conclusions.

Explain how you make the leap from reduced site occupancy to your Wigner lattice (or whatever lattice of charge carriers) expanding.

For bonus points, explain why it makes sense for charge carriers to "tunnel" from site to site--if all the sites are occupied! If the charge carriers are Fermions, it can't happen. You must have <100% site occupancy.

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JAG: "You keep bringing this up, but it makes no sense. Perhaps to you it does, but if that is the case, you are not communicating it well
An electron moves from a superconductor to a normal conductor contact. It scatters, creating resistance--IN THE NORMAL METAL. Wow, there is resistance in a normal metal in contact with a superconductor. Let's throw BCS out the door!"

JB: It makes perfect sense if you are able to understand simple physics. As I have pointed out in my MANUSCRIPT and HERE electrons in a vacuum diode also do not scatter but the voltage is not zero over the anode and cathode: i.e. the resistance is not zero. Resistance means dissipation of energy and generation of heat (look it up in any secondary school handbook on physics). Where do the vacuum electrons generate this resistance and heat? By scattering within the anode. This would be the case for any non-scattering charge carriers which have kinetic energy; they will scatter in the contact that they move into and this will register as energy disipation and a voltage must then be present over the contacts QED.


JAG: "No, charge carriers do accelerate in superconductors. One can even measure it.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9976680&dopt=Abstract"

JB: Of course they have to increase their velocity when the current increases. If this occurs through acceleration it is easy to prove by using Newton's laws (even nowadays available in secondary school textbooks - look it up) that their kinetic energy will increase. They will then scatter in the anodic contact and register a resistance. QED.

JAG: "You want to expell all electric field? You need a perfect conductor. Read part 2 of Halliday and Resnick. There is a section on capacitors."

JB: Very funny. It again proves that you are not understanding elementary physics. A perfect metal only acts as a perfect dielectric when an external electric field is applied; NOT when an electric field is applied by contacts so that a current flows through it. In the case of a superconductor the material MUST act as a pewrfect dielectric WHILE a current is flowing through it, or else the charge carriers will accelerate, scatter and register a resitance. QED.


JAG:"...and it fits experimental results that have been measured for ALL types of superconductors discovered to date" I'm sorry, where did your model actually fit the isotope effect in, say, tin? I don't recall that figure in your paper. I.e. where is a quantitative analysis of the isotope effect for a simple superconductor? You don't have it, so don't make this claim."

In order to do so one has to fit tin to Wigner's theory. This is not a new theory and by doing such an analysis would have made my manuscript too long and would have diluted its main thrust. For the Wigner orbitals to form, two localised energy levels must manifest at each orbital; with an energy gap between them (so you see also in this case an energy gap is predicted) to bind the electrons manifesting the orbital. As anybody witrh some knowledge of physics should know, localised electronic energy levels are mostly "vibronic": i.e. their values change with isotope mass. In fact, it is a standard method that is used in Solid State Physics to analyse such states; change the istope mass and measure the change in energy. Please read up on these aspects: it is clear that you have never encountered them before; but are notwithstanding criticizing me. You should be embarassed with yourself.

JAG: "Your model is high school algebra applied to unphysical assumptions. Two experts in the field have told you it is incorrect. Occam's razor tells me that the easiest decision was to take their advice and not read your paper--i.e. you are wrong. Not being a lazy scientist, I chose to read your paper."

JB: "If high school algebra is enough why use complicated Feynmann diagrams? As I have just now proved to you my assumptions are not unphysical; the fact that you think so rather illustrate to me that you should not have passed secondary school physics. The assumptions are simple and perfectly logical. "Two expertts" in the field DID NOT prove that my manuscript is wrong. REAL experts will not just state that my model is wrong but also give the reasons why. At least you tried, but you are obviously not an expert in Solid State Physics; nonetheless thanks for your efforts.

JAG: "Here's a trick for those of us second rate scientists who measure resistance of materials on a daily basis. Use a 4-point probe. You are making grandiose claims based on the fact that there is a resistance in your 2-point model. PRL would have rejected Bednorz and Mueller with their 4-point measurements. You can imagine that 2-point measurements wouldn't have gotten them into any journal."

JB: It seems that you do not understand even four-point measurements. Two are used to measure the voltage and it is then assumed that no current flows into these contacts. The other two are still used to inject and extract current, You will still have scatterring in the end contact so that an electric field will be present which can be measured with the voltmeter over the other two contacts.

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