Show that the total eigenfunction must be antisymmetric

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The discussion centers on demonstrating that the total eigenfunction for two noninteracting particles must be antisymmetric. It references the Pauli exclusion principle, which states that for fermions, the total eigenfunction must be antisymmetric under particle exchange. The spatial wavefunctions can be expressed as a combination of symmetric and antisymmetric forms, with the antisymmetric form necessary for indistinguishable particles. Participants express confusion over the wording of the question, particularly regarding the nature of the particles and the requirement for antisymmetry. Clarification is provided that the particles are indeed indistinguishable, necessitating the antisymmetric property when they are exchanged.
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Homework Statement


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By considering the eigenfunctions for 2 noninteracting particles at distances r1 and r2,
show that their total eigenfunction must be antisymmetric.
.

Homework Equations



Spatial wavefunctions:

Ψ(x1,x2) = 1/√2 [ ψA(x1B(x2) ± ψA(x2B(x1)]

Where + gives a symmetric wavefunction and - gives an antisymmetric one.




The Attempt at a Solution


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Hi, not really sure what to do with this one. I know that the Pauli exclusion principle says that the total eigenfunction must be antisymmetric for fermions. But the question doesn't mention fermions, just "2 noninteracting particles". I also know that the antisymmetric spin wavefunctions are associated with the symmetric spatial wavefunctions, and vice versa, to produce a total antisymmetric wavefunction, but I don't get why, which is what the question seems to be asking...

 
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The question is very poorly worded. The wave function is anti-symmetric with respect to what? Bad questions have no good answers :frown:
 
DrClaude said:
The question is very poorly worded. The wave function is anti-symmetric with respect to what? Bad questions have no good answers :frown:

Hi, sorry, I should probably have said a bit more in my OP. Presumably, in the question, the 2 particles are indistinguishable. So it means that eigenfunction must be antisymmetric under particle exchange. ie. that if the particles are swapped, this will give the negative of the original eigenfunction
 
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