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arXiv · 2608.08988

Modified Double Copy for Quasitopological Gravity with Matter

Valeri P. Frolov
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Abstract

We extend the modified double-copy construction to quasitopological gravity (QTG) coupled to matter. Spherically symmetric QTG solutions in $D$ dimensions are generated from an auxiliary gauge field in a flat $(D+1)$-dimensional spacetime. The gravitational field equations reduce to two relations determined by the QTG generating function and the matter stress--energy tensor. For a broad class of spherically symmetric matter sources, solutions of the auxiliary gauge-field equations can be used to construct exact solutions of the QTG field equations. The framework applies to Maxwell theory, nonlinear electrodynamics, and Yang--Mills theory, encompasses both static and Vaidya-type solutions, and reproduces the Einstein-gravity limit.

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Valeri P. Frolov. 2026-08-10. Modified Double Copy for Quasitopological Gravity with Matter. https://arxiv.org/abs/2608.08988

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