Time asymmetry in quantum mechanics: a pure mathematical point of view

Abstract

In the paper it is pointed out that ‘time asymmetry in quantum mechanics’ (TAQM) is an intrinsic element of the mathematical apparatus of quantum mechanics for semibounded Hamiltonians H with absolutely continuous spectrum coinciding with the positive half-line and of constant multiplicity. It is shown that the TAQM-semigroups are unsuitable for a spectral characterization of the resonances in terms of H.