I've been studying physics for many years now. Although I've made my living mostly as an engineer (mostly electronic, some optical, mechanical and software), my real interest is fundamental physics. In particular, how Quantum Mechanics, Relativity (Special and General) and Electromagnetism relate to each other. And especially how is it even possible that Quantum Mechanics is true?
This last issue is one of several issues that contributed to my dropping out of physics graduate school in the mid 1970's with just a Masters degree (University of Illinois, 1976). It was clear to me that there was much that was "true" in Quantum Mechanics. It is able to calculate certain measurable results to phenomenal precision and that agree with experiments. On the other hand, how can such a probabilistic theory preserve conservation of energy not just statistically, but in detail for every interaction? In the 1970's I was not very articulate in expressing these concerns, and I didn't find anyone interested in discussing it.
After leaving graduate school I discovered the famous EPR Paper in Physical Review (see Wikipedia article on EPR_Paradox), but also read the response to it in the following month's issue (by Dirac? I don't recall who responded to this challenge to QM.) I was equally impressed by that response that QM was at least self consistent, although I still didn't understand how it could be both statistical and precisely conserve energy (for example). Since then I've read Bell's paper (see John Bell: On the problem of hidden variables in quantum mechanics) which showed that it is possible to distinguish between QM and a theory of hidden variables. The idea of hidden variables was attractive to me then. Then in the 1980's results started appearing showing that these statistical tests favored QM. Gradually, as these tests got stronger and stronger it became clearer and clearer that QM was giving the correct results and the sort of "local, hidden variable" theories that I was looking for did not.
As I thought about all this I realized that my central issue was the interpretation of the wave function. As I read more and gained a deeper understanding it became crystal clear that there is nothing "real" about the wave function, and that it's collapse does not represent any change in the physical world. Yet there is clearly something meaningful represented by the wave function. QM uses it to make calculations that are confirmed by experiment to exquisite precision.
One thought experiment I considered is a photon from a distant star diffracting around the moon and being detected on earth. Astronomers have observed these diffraction fringes, so we know that, somehow, each photon "knows" about the size and shape of the moon by the time it arrives on earth. Yet, I thought, what if the photon was destined to be absorbed on a mountain peak on the moon instead being detected on earth? How does each photon "know" that the energy in the photon must end up on the moon and not in the detector? (Excuse the anthropomorphic statements, I find it easier to express it this way. I do NOT intend to imply that there is any sort of consciousness associated with photons!) High energy physics experiments are pretty clear that any process that emits a single photon always results in ONE photon being detected anywhere, not sometimes two and occasionally none. Yet the wave function is a statistical thing. How does this work? Also, if an electron in an atom has a wavefunction that is a superposition of several energy eigenstates, and then a measurement is made that puts the electron in a single energy state, how is it that energy is conserved? And if an excited state of an atom is in an indefinite energy state (due to the lifetime of the state), how is energy conserved in that case? I still don't have a good answer to that, although some vague ideas are forming. More about that much later.
I am also interested in relativity, both Special and General. And how QM is, to some degree, incompatible with GR. At least, people say that when talking about trying to quantize gravity. I'll admit right now that I haven't been able to make sense of QED. I've read Feynmans books, and a number of text books on the subject, but find the MEANING of the mathematics impenetrable, so far. Again, there is clearly something "true" about QED, I just am having great difficultly seeing through the math to the physics.
It was while pondering this issue that I started to makes some small progress in figuring things out. I don't claim to have it all figured out yet! Just a few small things here and there that either I can now understand how they relate to each other, or have found at least one mechanism that might account for how it appears to work. In this blog I plan to present some of my ideas, and the calculations I did to show that they are consistent with current experimental evidence.
I would appreciate any feedback anyone has on these posts. I'm looking for critical comments and questions, not necessarily for affirmation of these ideas. If something isn't clear and convincing, I want to know about it. If something is WRONG, I especially want to hear about it. Finally, it would be nice to know that someone out there is reading my posts, other than a disk drive at Google!
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