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arXiv · 2003.08398

Well-posed formulation of Lovelock and Horndeski theories

Aron D. Kovacs·Harvey S. Reall
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Abstract

We study the initial value problem for Lovelock and Horndeski theories of gravity. We show that the equations of motion of these theories can be written in a form that, at weak coupling, is strongly hyperbolic and therefore admits a well-posed initial value problem. This is achieved by introducing a new class of "modified harmonic" gauges for general relativity.

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Aron D. Kovacs, Harvey S. Reall. 2020-03-18. Well-posed formulation of Lovelock and Horndeski theories. https://doi.org/10.1103/physrevd.101.124003

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