Are Identical Non-Interacting Particles Distinguishable?

[Cryxic]

I just wanted to clarify something conceptual with non-interacting particles. So if you have three identical non-interacting fermions (say electrons), is it true that they are distinguishable (since they're non-interacting)? Or are they indistinguishable since they're still identical?

 

[xepma]

No, the indistinguishability of the electrons is also present in the absence of interactions. Any wavefunction of the electrons is anti-symmetrized. So although the electrons do not interact, they still feel some form of repelment as they cannot occupy the same state.

It's ofcourse a mathematical statement, since non-interacting particles can hardly be considered physical.

 

[Cryxic]

No, the indistinguishability of the electrons is also present in the absence of interactions. Any wavefunction of the electrons is anti-symmetrized. So although the electrons do not interact, they still feel some form of repelment as they cannot occupy the same state.

It's ofcourse a mathematical statement, since non-interacting particles can hardly be considered physical.

Ok thanks. So basically: even though they're non-interacting, they're still indistinguishable and they obey the Pauli exclusion principle. Correct?

 

[xepma]

Yes, indeed.