Thursday, November 22, 2012

I reply to Prof. Sipe's objections

In my last post, I talked about my meeting with Prof. John Sipe at the U of T two years ago. In our meeting, I had listed six phenomena which I considered the "litmus test" for any interpretation of Quantum Mechanics. In particular, if you want to challenge the Copenhagen Interpretation, you must be able to explain these phenomena.

At the end of our meeting, I claimed to have explained five of the six phenomena on my list by means of ordinary time-evolution of the wave function, avoiding any type of collapse, probability or quantum leap type of events. Professor Sipe didn't really question the correctness of my explanations. His real objection was that I hadn't brought forth anything particularly new or ground-breaking. In particular he said that:

1. There were many well-knwon semi-classical explanations for the Compton effect, including the obvious vxB force which clearly transfers momentum from an e-m wave to an electron.

2. The operation of a Geiger Counter was no more than a type of photo-electric effect, for which many authorities had already published semi-classical explanations.

Since we were out of time, I told Professor Sipe that I would write him a letter answering these objections. Here is what I wrote him:

"A few points came up that I was not able to deal with at the time, but I have had a chance to think them over and would like to give you my viewpoint. First of all, there was the idea that you can explain the Compton effect with a v x b type of argument. At the time I said it was an awful explanation and I'm even more convinced after thinking it over, especially when you contrast it with the multilayer diffraction grating (?) model of Schroedinger.

"There are so many flaws in the v x b argument that it is hard to know where to begin. For one thing it gives a smeared-out frequency spectrum for the scattered light. Since the electron is slowly and gradually accelerated by successive wavefront impulses, the doppler frequency shift of the re-radiated light is constantly changing. Compare this with the Schroedinger picture where you get interaction between the light and particle waves only when they have identical wavelengths (COM reference frame). The frequency shift in the scattered light comes out perfectly and cleanly.

"There are a host of problems with the vxb argument and they all stem essentially from trying to mix apples and oranges: the light is a wave but what is the electron, a tiny charged ping-pong ball? How does the vxb argument account for glancing collisions where the light and electron move off at different angles? Most seriously, if the electron is a point charge, then once it is set in motion by the incoming e-m wave, it re-radiates spherically. This spherical radiation cannot possibly cancel out the incoming e-m wave: only a plane-wave-versus-plane-wave (photon vs electron) system can do this.

"More importantly there was the question of why I think my explanation of the geiger counter offers a fundamentally new paradigm as opposed to the existing semi-classical explanations of the photo-electric effect. Superficially these phenomena might seem to have much in common: there are two metal plates, and an electron is freed from one and captured at the other.

"In fact, so far as I know the existing semi-classical arguments have one fundamental weakness: at some point or another, they invoke the Born Postulate. Mott does it in explaining the straight line cloud tracks. Jaynes does it (so far as I understand) for the photoelectric effect to explain prompt emission. I have a paper by Ballentine in front of me where he proudly dismisses the need for the "collapse of the wave function" by showing how the probability interpretation (the Born Postulate) handles everything. My question is: what is the Born Postulate if not just a rephrasing of the Wave Function Collapse, which in itself was just a rehash of Bohr's original Quantum Leap? To me they are all the same.

"Furthermore, I don't think people working in this field would equate the geiger effect and the photo-electric effect. Schroedinger himself was confident in his wave explanation of the photo-electric, but Born and Heisenberg at least made the Geiger Counter example a centerpiece of their argument against Schroedinger's picture. Bitbol discusses this at some length in the very first chapter of his book (Schroedinger's Philosophy of Quantum Mechanics) and I believe when he quotes Schroedinger has expressing "the hope that the future will solve this riddle in a satisfactory way" (p. 10), that it is precisely the Geiger Counter problem that he is talking about. He's certainly not talking about the photo-electric effect.

"If Schroedinger had thought that the geiger counter could be explained via the natural time-evolution of the wave function, as I have explained it, he would not have written his famous paper of 1935 (the Cat paper). My explanation of the Geiger Counter mechanism effectively answers the question of Schroedinger's Cat because it shows that while the radon and radium atoms are in a superposition, continuously emmiting alpha and gamma waves, that the clicking of the geiger counter is a classically discrete event which is randomly (in the classical sense of "randomly") stimulated by the continuous low-intesity irradiation of the gas in the geiger counter. So the dead and the live cat are never entangled with the radon/radium superposition.

"In summary, if anyone else has already come up with my mechanism for Quantum Siphoning, then the explanation for Schroedinger's Cat would have followed as night follows day. I do not believe such an explanation would have gone unnoticed in even the popular literature, and therefore I am quite sure that my explanation is original."

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