Subject: Pauli Exclusion Principle inconsistent with electron localization

The Pauli exclusion principle asserts that the total electron wave function is 
antisymmetric (equivalently, only two electrons, with opposite spins, can 
occupy the same orbital).  But suppose I have two separate hydrogen atoms and 
let them interact to form a hydrogen molecule.  At what point does the wave 
function become antisymmetric?  The permutation group is discrete, so becoming 
antisymmetric is an all-or-none process, inconsistent with "intermediate 
excited states" and the like while the molecule is forming.  
It seems to be necessary to suppose that the electron wave function is 
antisymmetric even before the two atoms interact, but no chemist would believe 
this.  For one thing, it flies in the face of any notion of electron 
localization.

Re: Pauli Exclusion Principle inconsistent with electron localization