The SME with gravity and explicit diffeomorphism breaking
arXiv:1911.02517
Abstract
This overview looks at what happens when the Standard-Model Extension (SME) is used to investigate gravity theories with explicit diffeomorphism breaking. It is shown that when matter-gravity couplings are included, the SME generally maintains consistency with the Bianchi identities, and it therefore provides a useful phenomenological framework for investigating the effects of explicit diffeomorphism breaking in gravity theories.
Proceedings of the 8th Meeting on CPT and Lorentz Symmetry