Three Plus Anti-symmetric Particles

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SUMMARY

The discussion focuses on the behavior of fermions, specifically their anti-symmetry under exchange when dealing with three or more particles. It is established that the total wavefunction of indistinguishable fermions must reverse sign upon the exchange of any two particles. This principle applies to any pair of particles within a system of three or more, ensuring that the wavefunction remains anti-symmetric. The mathematical representation of this concept is encapsulated in the notation of the N-particle fermionic wave function, which incorporates both position and spin components.

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JohnH
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So I understand that fermions are anti-symmetric under exchange, but in the contexts I've seen this explained they were always talking about two particles, or at least two wavefunctions. I'm curious how this works when there are three or more particles. Is any two given pairs of those 3+ particles anti-symmetric under exchange or is it more systematic? Or is it that there's essentially one wavefunction for all the particles (quanta of energy) in one spin and another wavefunction for all the quanta of energy in the other spin such that it's just those two wavefunctions that are anti-symmetric under exchange?
 
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JohnH said:
So I understand that fermions are anti-symmetric under exchange, but in the contexts I've seen this explained they were always talking about two particles, or at least two wavefunctions. I'm curious how this works when there are three or more particles.
The wave function for three electrons is covered here:

https://galileo.phys.virginia.edu/classes/752.mf1i.spring03/IdenticalParticlesRevisited.htm

The total wavefunction must reverse sign under the exchange of any two particles.
JohnH said:
Is any two given pairs of those 3+ particles anti-symmetric under exchange or is it more systematic? Or is it that there's essentially one wavefunction for all the particles (quanta of energy) in one spin and another wavefunction for all the quanta of energy in the other spin such that it's just those two wavefunctions that are anti-symmetric under exchange?
I can't make any sense of this part of your question.
 
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PeroK said:
I can't make any sense of this part of your question.
Yeah, just trying to answer my own question last minute. Probably better off waiting for an answer. Anyway, thank you for it.
 
The wave functions of indistinguishable fermions must be antisymmetric under exchange of any pair of arguments, ##(\vec{x}_j,\sigma_j##, where ##\vec{x}_j## is the postition and ##\sigma_j## the spin-##z##-component (##\sigma_j\in \{-s,-s+1,\ldots,s-1,s \}##, where ##s## is a half-integer positive number, ##s \in \{1/2,3/2,\ldots \}##), i.e., if ##\psi(t,\vec{x}_1,\sigma_1;\vec{x}_2,\sigma_2;\ldots; \vec{x}_N,\sigma_N)## is an ##N##-particle fermionic wave function, then it's antisymmetric by exchanging any pair ##(\vec{x}_i,\sigma_i)## and ##(\vec{x}_j,\sigma_j)##.
 
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