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arXiv · 1307.2234

Chiral and Gravitational Anomalies on Fermi Surfaces

Gokce Basar·Dmitri E. Kharzeev·Ismail Zahed
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Abstract

A Fermi surface threaded by a Berry phase can be described by the Wess-Zumino-Witten (WZW) term. After gauging, it produces a five-dimensional Chern-Simons term in the action. We show how this Chern-Simons term captures the essence of the Abelian, non-Abelian, and mixed gravitational anomalies in describing both in- and off-equilibrium phenomena. In particular we derive a novel contribution to the Chiral Vortical Effect that arises when a temperature gradient is present. We also discuss the issue of universality of the anomalous currents.

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Gokce Basar, Dmitri E. Kharzeev, Ismail Zahed. 2013-07-08. Chiral and Gravitational Anomalies on Fermi Surfaces. https://doi.org/10.1103/physrevlett.111.161601

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