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arXiv · 2003.13847

Angle deficit & non-local gravitoelectromagnetism around a slowly spinning cosmic string

Abstract

Cosmic strings, as remnants of the symmetry breaking phase in the Early Universe, may be susceptible to non-local physics. Here we show that the presence of a Poincar\'e-invariant non-locality -- parametrized by a factor $\exp(-\Box\ell^2)$ -- regularizes the gravitational field and thereby changes the properties of spacetime: it is now simply connected and the angle deficit around the cosmic string becomes a function of the radial distance. Similar changes occur for the non-local gravitomagnetic field of a rotating cosmic string, and we translate these mathematical facts into the language of non-local gravitoelectromagnetism and thereby provide a physical interpretation. We hope that these insights might prove helpful in the search for traces of non-local physics in our Universe.

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Jens Boos. 2020-03-30. Angle deficit & non-local gravitoelectromagnetism around a slowly spinning cosmic string. https://doi.org/10.1142/s0218271820430270

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