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arXiv · 1201.5732

Anomalies, boundaries and the in-in formalism

Ian G. Moss
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Abstract

In the context of quantum field theory, an anomaly exists when a theory has a classical symmetry which is not a symmetry of the quantum theory. This short exposition aims at introducing a new point of view, which is that the proper setting for anomaly calculations is the `in-in', or closed-time path formulation of quantum field theory. There are also some new results for anomalies in the context of boundary value problems, and a new correction to the $a_5$ heat-kernel coefficient.

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Ian G. Moss. 2012-01-27. Anomalies, boundaries and the in-in formalism. https://doi.org/10.1088/1751-8113/45/37/374022

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