A Do Alpha and Beta Spins Commute in Quantum Mechanics?

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Dear Everyone,

A simple question. Do α and β spins commute? In other words, can we say αβ = βα ?

Thank you for your help.
 
sams said:
A simple question. Do α and β spins commute? In other words, can we say αβ = βα ?
What are α and β? And are you considering one or two particles (not that it will make much of a difference, but some context would be nice)?
 
DrClaude said:
What are α and β? And are you considering one or two particles (not that it will make much of a difference, but some context would be nice)?

Many thanks Dr. Claude for your reply.

α and β represent the spins of an electron.

We are considering here a system of two electrons (i.e. Helium atom).
The spin wavefunction of a triplet state (S=1 and Ms = 0) is written as:
|S,Ms> = |1,0> = 1/21/21β2 + β1α2)

Is it the same if we write:
|S,Ms> = |1,0> = 1/21/21β2 + α2β1) ?
 
sams said:
Is it the same if we write:
|S,Ms> = |1,0> = 1/21/21β2 + α2β1) ?
Yes. These are spin states, so equivalent to wave functions, and not operators. The order is of no importance.
 
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DrClaude said:
Yes. These are spin states, so equivalent to wave functions, and not operators. The order is of no importance.

Thank you once again Dr. Claude for your reply and support.
 
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