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arXiv · 1206.5218

Comments on Chern-Simons Contact Terms in Three Dimensions

Cyril Closset·Thomas T. Dumitrescu·Guido Festuccia·Zohar Komargodski·Nathan Seiberg
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Abstract

We study contact terms of conserved currents and the energy-momentum tensor in three-dimensional quantum field theory. They are associated with Chern-Simons terms for background fields. While the integer parts of these contact terms are ambiguous, their fractional parts are meaningful physical observables. In N=2 supersymmetric theories with a U(1)_R symmetry some of these observables lead to an anomaly. Moreover, they can be computed exactly using localization, leading to new tests of dualities.

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Cyril Closset, Thomas T. Dumitrescu, Guido Festuccia, Zohar Komargodski, Nathan Seiberg. 2012-06-22. Comments on Chern-Simons Contact Terms in Three Dimensions. https://doi.org/10.1007/jhep09(2012)091

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