What is the Pauli exclusion principle?

Pauli exclusion principle is actually an inference of Fermi-Dirac statistics, one of the two quantum statistics, and its essence is interference cancellation of specific wave functions. This cancellation is essentially the same as the light wave cancellation at the dark line in the double-slit interference experiment of light. Can we say that photons repel each other at dark lines? Therefore, even if you regard this interference cancellation as a kind of "repulsion", it is different from the general force.

First of all, no one can explain this problem clearly, because no one really understands quantum mechanics, including the top physicists. Bohr once said: "If anyone is not carried away by quantum mechanics, he must not understand quantum mechanics." Einstein said: "I have been thinking about quantum mechanics for a hundred times longer than general relativity, but I still don't understand." Feynman, a genius, said that he knew he could do it, but he didn't know why! What I say below, I hope to be inspired; There may be misleading elements, although I am trying to avoid them, but after all, the standard language for describing physics is mathematics, not ordinary everyday language. In some places, I can't help but use vague and wrong descriptions.

What does it mean that microscopic particles are waves at the same time? Personally, I think the Feynman path integral form of quantum mechanics shows a particularly amazing picture, but it is helpful to understand the essence of the problem. This strange scene is roughly like this: every particle (for example, an electron) is incarnated a million times at every moment, each incarnate particle explores a specific path with the fluctuation characteristics of the original particle infinitely fast, all incarnate particles explore all paths in time and space, and then each incarnate particle returns to "submit a detection report" according to the length, direction and situation encountered on the way, and summarizes all reports of all incarnate particles to get the corresponding path. The summary of the report will definitely point out that the path through another electron with exactly the same quantum number is forbidden, because of complete interference and cancellation, so the electron will not actually take these paths that will encounter the same electron at all.

The above is the case of a fermion with a semi-integer spin, while a boson with an integer spin is not interference cancellation at any time, but constructive interference, that is, it does not show some repulsion, but gravity. The reason for this difference is that the internal space (expressed by intrinsic spin) is different, and the internal and external space are related, so the external wave function is also different. On the premise of satisfying the special relativity requirements of regular quantum mechanics and Lorentz transformation, through a series of mathematical deduction, it is found that particles should have intrinsic spins and be divided into bosons (following bose-einstein statistics) and fermions (following Fermi-Dirac statistics).

From the point of view of quantum mechanics, the superposition interference of waves is everywhere. The dielectric particles of the four basic forces are only four special bosons, all of which participate in the superposition and interference of the corresponding fluctuations without exception. From this point of view, the force shown by interference is more basic than the four basic forces!

This is how the universe embodies its unparalleled grandeur-when human beings have tried their best to turn a question mark into an exclamation point, the universe has prepared more question marks to give back to human beings. You can keep asking questions (this process is full of excitement, surprise, frustration and anger), but the question mark will only increase, and you will never see the day when the question mark runs out.