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arXiv · 1407.1690

Time-ordered exponential on the complex plane and Gell-Mann -- Low formula as a mathematical theorem

Shinichiro Futakuchi·Kouta Usui
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Abstract

The time-ordered exponential representation of a complex time evolution operator in the interaction picture is studied. Using the complex time evolution, we prove the Gell-Mann -- Low formula under certain abstract conditions, in mathematically rigorous manner. We apply the abstract results to quantum electrodynamics with cutoffs.

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Shinichiro Futakuchi, Kouta Usui. 2014-07-07. Time-ordered exponential on the complex plane and Gell-Mann -- Low formula as a mathematical theorem. https://arxiv.org/abs/1407.1690

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