Just want to clarify my understanding of these things.(adsbygoogle = window.adsbygoogle || []).push({});

Fermions obey the Pauli Exclusion Principal, meaning meaning only one particle can occupy a single state. This means the wave function is anti-symmetric under particle exchange. That's the part that isn't making much sense. Is it because if we have two particles designated by quantum numbers n, l, m_{1}and n, l, m_{2}and we swap the particles the only way for the states to be different is if m_{1}= -m_{2}?

Also, when we speak of the state of a system...

Consider the basic problem of a spin 1/2 particle in a constant magnetic field (0, 0, B).

H = γS_{z}, γ = geB/2mc, or something like that..

We write H|E> = E|E>

H^{2}|E> = E^{2}|E>

From this we determine the eigenvalues E_{1}and E_{2}, and the state at some time t is given by

|ψ> = C_{+}e^{aE1t}|E_{1}> + C_{-}e^{aE2t}|E_{2}>

What does this actually mean? Is it the energy at some later time t? The spin?

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# A few QM questions

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