(May 31, 2017 10:59 PM)Syne Wrote: [ -> ]The fermion/boson dichotomy is an empirical fact. Things that can simply be demonstrated can be known before the theoretical underpinning are fully established. And all your talk about QFT is just arm-waving, superfluous in answering the question originally asked.
Sorry, Syne, I really hate to do this to you. I am, though, mindful that you are mentally weaker and tend to be more emotional...due to your evolutionary psychology, but it’s for your own good.
Pauli Exclusion Principle
The Pauli exclusion principle is the quantum mechanical principle which states that two or more identical fermions (particles with half-integer spin) cannot occupy the same quantum state within a quantum system simultaneously. In the case of electrons in atoms, it can be stated as follows: it is impossible for two electrons of a poly-electron atom to have the same values of the four quantum numbers: n, the principal quantum number, the angular momentum quantum number, the magnetic quantum number, and the spin quantum number. For example, if two electrons reside in the same orbital, and if their n, ℓ, and mℓ values are the same, then their ms must be different, and thus the electrons must have opposite half-integer spins of 1/2 and −1/2.
This principle was formulated by Austrian physicist Wolfgang Pauli in 1925 for electrons,
and later extended to all fermions with his spin-statistics theorem of 1940.
Bose-Einsein Statistics
Particles with an integer spin, or bosons, are not subject to the Pauli Exclusion Principle: any number of identical bosons can occupy the same quantum state, as with, for instance, photons produced by a laser and Bose–Einstein condensate.
The theory of this behaviour was developed (1924–25) by Satyendra Nath Bose, who recognized that a collection of identical and indistinguishable particles can be distributed in this way. The idea was later adopted and extended by Albert Einstein in collaboration with Bose.
He sent the manuscript to Albert Einstein requesting publication in the Zeitschrift für Physik. Einstein immediately agreed, personally translated the article from English into German (Bose had earlier translated Einstein's article on the theory of General Relativity from German to English), and saw to it that it was published. Bose's theory achieved respect when Einstein sent his own paper in support of Bose's to Zeitschrift für Physik, asking that they be published together.
This was done in 1924.
Syne Wrote:Light has no proper frame of reference, so you cannot really make assertions about it. Such thought experiments are fanciful, not factual. Light simply doesn't not experience...period.
It’s was a thought experiment for a fanciful candle, Syne. I got the idea from Ethan Siegal.
Nothing happens at once. At once is not everywhere. Only light is everywhere and everywhere at once.
It's good.
