The phase of the scattering operator from the geometry of certain infinite-dimensional groups
arXiv:1403.4340 · doi:10.1007/s11005-014-0714-1
Abstract
We revisit the computation of the phase of the Dirac fermion scattering operator in external gauge fields. The computation is through a parallel transport along the path of time evolution operators. The novelty of the present paper compared with the earlier geometric approach by Langmann and Mickelsson, [LM], is that we can avoid the somewhat arbitrary choice in the regularization of the time evolution for intermediate times using a natural choice of the connection form on the space of appropriate unitary operators.
9 pages, no figures