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Of course, the new theory is not without its complications:
Now, Rabi Mohapatra from the University of Maryland and Salah Nasri from the University of Florida say that the two results can be reconciled if one considers the source of the axions. Whereas in the PVLAS experiment axions would have been produced locally in the laser beam at room temperature or colder, the CAST experiment was monitoring axions produced in the Sun's core at about 10 million degrees Celsius.
Mohapatra's theory is that a phase transition could occur at Sun's high temperatures that destroys the coupling altogether, rather like a magnet losing its magnetism when heated. This would account for the null findings of CAST. However, this theory would also require a new particle - a force-carrying boson with a mass of about 100 MeV - to account for the coupling observed in PVLAS. Although such a particle has not been seen, Mohapatra says that it could be sought in future experiments involving the decay of upsilon particles.
I'm just not crazy about the idea of resolving a discrepancy between two experiments looking for a hypothetical particle that nobody has conclusively seen by introducing yet another hypothetical particle that nobody has seen. As I said before, I don't think that Occam's Razor is a decisive principle in science, but I'd really like to think that there might be a simpler explanation than that. There are lots of problems that can be fixed if you just posit new particles and forces, but at some point, you're just accumulating epicycles, and need to start over.
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How can Euclid be modified such that cartographers could project the curved surface of the Earth upon continuous flat paper without distortion? Observation not theory dictates reality.
Physics diverged in the 1930s. Galileo, Newton, and Einstein demanded parity-even spacetime. Cartan, Weitzenböck... affine, teleparallel, non-commutative gravitation theories allow parity-odd spacetime. The disjoint non-overlap is testable to high sensitivity.
Post-Big Bang inflation is driven by the chiral pseudoscalar field (thereby diluted to contemporary values), matter/antimatter skew is sourced, Weak Interaction asymmetry is sourced, biological homochirality is sourced. Physics is subtly rewritten parity-odd and contradictions become predictions. One's chance of finding a dropped coin at night is not where the light is brightest, it is where the coin has been dropped. Somebody should look.
Sounds a bit like the Star Trek syndrome, if I may coin a phrase. Any time an episode of Next Generation was getting out of hand, SHAZAM! a new particle would fix the problem!
Adding extra particles to make the theory work reminds me of the ad hoc explanations of the Michelson experiment before Einstein developed relativity. Lorentz developed his contraction as a physical contraction of an object while moving, and then added time dilation to resolve the discrepancies. Once you start adding energy and momentum fixes to the problem, it starts to look like fitting an N-point curve with N-parameters.
I'm not sure that introducing more particles is consistent with Occam's Razor anyway. After all, what the razor really says is "entities should not be multiplied unnecessarily."