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arXiv · 1907.12595

Lorentz-violating gravity and the bootstrap procedure

Michael D Seifert
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Abstract

In conventional gravitational physics, the so-called "bootstrap procedure" can be used to extrapolate from a linear model of a rank-2 tensor to a full non-linear theory of gravity (i.e., general relativity) via a coupling to the stress-energy of the model. In this work, I extend this procedure to a "Lorentz-violating" gravitational model, in which the linear tensor field and the matter fields "see" different metrics due to a coupling between the tensor field and a background vector field. The resulting model can be thought of as a generalized Proca theory with a non-minimal coupling to conventional matter. It has a similar linearized limit to the better-known "bumblebee model", but differs at higher orders in perturbation theory. Its effects are unobservable in FRW spacetimes, but are expected to be important in anisotropic cosmological spacetimes.

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Michael D Seifert. 2019-07-29. Lorentz-violating gravity and the bootstrap procedure. https://doi.org/10.1088/1361-6382%2Fab53ef

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