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arXiv · 2403.17977

Abelian Chern-Simons term as a Kaluza-Klein dimensional reduction of the Gibbons-Hawking surface term

Hongsu Kim·Jae Sok Oh
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Abstract

It is suggested that the original, minimal Kaluza-Klein theory should be extended by adding a 5-dimensional version of the Gibbons-Hawking gravitational surface term. It is then demonstrated that the usual dimensional reduction of the newly added surface (boundary) term leads to the emergence of the famous Abelian Chern-Simons term. It is stressed that the advent of this Chern-Simons term is not merely a parametrization artefact but a real thing. Finally, the issue of finite-ranged electromagnetic interaction due to massive photons on a plane has been interpreted in terms of the violation of the local gauge invariance of this extended version of Kaluza-Klein theory.

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Hongsu Kim, Jae Sok Oh. 2024-03-22. Abelian Chern-Simons term as a Kaluza-Klein dimensional reduction of the Gibbons-Hawking surface term. https://arxiv.org/abs/2403.17977

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