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arXiv · 2011.11868

Topological violation of global symmetries in quantum gravity

Kazuya Yonekura
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Abstract

We discuss a topological reason why global symmetries are not conserved in quantum gravity, at least when the symmetry comes from compactification of a higher form symmetry. The mechanism is purely topological and does not require any explicit breaking term in the UV Lagrangian. Local current conservation does not imply global charge conservation in a sum over geometries in the path integral. We explicitly consider the shift symmetry of an axion-like field which originates from the compactification of a $p$-form gauge field. Our topological construction is motivated by the brane/black-brane correspondence, brane instantons, and an idea that virtual black branes of a simple kind may be realized by surgery on spacetime manifolds.

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Kazuya Yonekura. 2020-11-24. Topological violation of global symmetries in quantum gravity. https://doi.org/10.1007/jhep09(2021)036

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