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arXiv · 1403.4340

The phase of the scattering operator from the geometry of certain infinite-dimensional groups

Jouko Mickelsson
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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.

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Jouko Mickelsson. 2014-03-18. The phase of the scattering operator from the geometry of certain infinite-dimensional groups. https://doi.org/10.1007/s11005-014-0714-1

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