Density-curvature response and gravitational anomaly

Andrey Gromov; Alexander G. Abanov

doi:10.1103/physrevlett.113.266802

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arXiv · 1403.5809

Density-curvature response and gravitational anomaly

Andrey Gromov·Alexander G. Abanov

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Abstract

We study constraints imposed by the Galilean invariance on linear electromagnetic and elastic responses of two-dimensional gapped systems in background magnetic field. Exact relations between response functions following from the Ward identities are derived. In addition to viscosity-conductivity relations known in literature we find new relations between the density-curvature response and the chiral central charge.

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Andrey Gromov, Alexander G. Abanov. 2014-03-23. Density-curvature response and gravitational anomaly. https://doi.org/10.1103/physrevlett.113.266802

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