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arXiv · 2409.00178

Generalised symmetries in linear gravity

Chris Hull·Maxwell L Hutt·Ulf Lindström
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Abstract

Linearised gravity has a global symmetry under which the graviton is shifted by a symmetric tensor satisfying a certain flatness condition. There is also a dual symmetry that can be associated with a global shift symmetry of the dual graviton theory. The corresponding conserved charges are shown to satisfy a centrally-extended algebra. We discuss the gauging of these global symmetries, finding an obstruction to the simultaneous gauging of both symmetries which we interpret as a mixed 't Hooft anomaly for the ungauged theory. We discuss the implications of this, analogous to those resulting from a similar structure in Maxwell theory, and interpret the graviton and dual graviton as Nambu-Goldstone modes for these shift symmetries.

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Chris Hull, Maxwell L Hutt, Ulf Lindström. 2024-08-30. Generalised symmetries in linear gravity. https://arxiv.org/abs/2409.00178

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