= Indistinguishable particles
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= Identical particle
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<Indistinguishable particles> have the same intrinsic particle properties, so exchanging their particle labels does not identify a different observable arrangement. Two <electrons> are an example; an <electron> and a <proton> belong to different species. Labels used as slots in a <wavefunction> are mathematical coordinates, not permanent identity tags.
For ordinary <identical particles> in three spatial dimensions, the <symmetrization postulate> takes the total <quantum state> to be symmetric for <bosons> or antisymmetric for <fermions>. In the antisymmetric case, exchanging all one-particle variables changes the sign of the <wavefunction> while leaving detection <probabilities> unchanged. The symmetry includes <spin> and other internal coordinates, not just position.
Spatial modes can nevertheless be addressed separately. Measuring the <spin> in one localized mode differs from measuring an imagined permanently labelled <electron>. <Conditional spin measurement of identical fermions> makes that distinction explicit. In two spatial dimensions, <anyons> allow more general exchange behavior; the boson/fermion alternative is not an unrestricted statement about every dimension.
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