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arXiv · 2004.07613

NUT charge in linearized infinite derivative gravity

Abstract

We study the gravitational field of the NUT-like source in the linearized (ghost-free) infinite derivative gravity. Such a source is equivalent to the spinning semi-infinite cosmic string with no tension. In general relativity, the linearized (massless) Taub-NUT solution has a curvature singularity as well as a topological defect corresponding to distributional curvature on one half of the symmetry axis called the Misner string. We find the NUT-charged spacetime in the linearized infinite derivative gravity. We show that it is free from curvature singularities as well as Misner strings. We also discuss an asymptotic limit along the symmetry axis that leads to the spacetime of a spinning cosmic string of infinite length.

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Ivan Kolar, Anupam Mazumdar. 2020-04-16. NUT charge in linearized infinite derivative gravity. https://doi.org/10.1103/physrevd.101.124005

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