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Unobserved Charged Particles
It is a common occurence in science news that an article announces that an experiment shows that particles only have a physical existence when they are measured. Such sensationalistic announcements stem from two sources. One is the desire of science journalist, like all journalists, for sensationalist headlines. The other is from the proponents of the Copenhagen Interpretation of quantum physics. This group is developing into a cult.
At a recent conference of particle physicists the participants were surveyed as to what theory of quantum reality they adhered to. Only 42 percent said The Copenhagen Interpretation (CI) . This means that 58 percent thought the evidence against the CI was more persuasive than the evidence for it.
The strict logic of experimental confirmation indicates that an assertion than an experiment would show that particles have a physical existence only when they are measured is undoubtedly incorrect. Consider the logic of confirmation. If Proposition A implies Event B should occur and Event B is found to occur that does not mean that Proposition A is necessarily true. It means only that Proposition A might be true. To establish that Proposition A is necessarily true it would have to be established that Event B would occur only if Proposition A were true. This is a proposition that would be very difficult to establish and it cannot be done by experiments. In practise there may well be alterntive explanations why Event B would occur.
Likewise if Proposition A and Proposition C imply Event B should occur and Event B does not occur that does not mean Proposition A is necessarily false. It means Proposition A or Proposition C is false.
The Bell Inequality Theorem for charged particles is based on, among other things, that such particles have a continuous material existence. When the Bell Inequality was not confirmed that was erroneously taken to prove the nonmaterial existence of charged particles. But the derivation of the Bell Inequality also assumed charged particles travel in strictly straight lines with no tranverse oscillations. But charged particles in a beam are repelled from nearest neighbors and that creates transverse oscillations. Incidently much of the testing of Bell's Theorem involves photons and the material existence of photons has never been in consideration.
Quantum physics has been based since about 1926 on solutions to Schrödinger's time-independent equation. Bohr and his group correctly interpreted such solutions as wavefunctions whose squared value is the probability density function for the physical system. The notion that material particles may have periods of no material existence arose from the erroneous assertion by Bohr that a material particle cannot have a probability density distribution. In fact any particle in motion has a probability density representing the probabities of finding the particle in the various intervals of its trajectory at a randomly chosen time.
The Correspondence Principle requires spatial average of the quantum results be asymptoticaly equal to the results of Classical analysis. The quantum results are probability density distributions so the corresponding Classical probability density distributions have to be based upon the proportions of the time the Classical system spends in the portions of its trajectory. That is what can be called its time-spent probability density distribution.
Later when Bohr's associate Werner Heisenberg discovered the Uncertainty Principle this was taken as evidence for the immateriality of particles. This is also erroneous. The time-spent probability density functions for simple material physical systems that can be solved for easily satisfy the Uncertainty Principle.
It has been shown that a wavefunction solution to Schrödinger time-independent equation is equal to a product of two functions. One function corresponds to the wave function associated with the Classical time-spent probability density distribution. The other function is asymptotically equal to a solution to Helmholtz' equation which is a pure sinusoidal function whose squared values spatially average out to a constant.
The time-spent probability density distributions give the dynamic appearance of a physical system. That dynamic appearance does not affect the static nature of the system. A rapidly spinning fan may look like an unchanging translucent disk that is a single particle, but the fan's static nature is still the physically material fan.
The role of measurement is that measurement may involve stopping the motion of the object. Sticking a solid object into a rapidly spining fan appears to change it from an unchanging translucent disk into a solid motionless fan.
Thus there never has been and cannot be any experimental evidence that charged particles have a material existence only when measured. Such a proposition is not only wrong; it is silly wrong.
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