Recognition: unknown
Gravity with a dynamical preferred frame
read the original abstract
We study a generally covariant model in which local Lorentz invariance is broken "spontaneously" by a dynamical unit timelike vector field $u^a$---the "aether". Such a model makes it possible to study the gravitational and cosmological consequences of preferred frame effects, such as ``variable speed of light" or high frequency dispersion, while preserving a generally covariant metric theory of gravity. In this paper we restrict attention to an action for an effective theory of the aether which involves only the antisymmetrized derivative $\nabla_{[a}u_{b]}$. Without matter this theory is equivalent to a sector of the Einstein-Maxwell-charged dust system. The aether has two massless transverse excitations, and the solutions of the model include all vacuum solutions of general relativity (as well as other solutions). However, the aether generally develops gradient singularities which signal a breakdown of this effective theory. Including the symmetrized derivative in the action for the aether field may cure this problem.
This paper has not been read by Pith yet.
Forward citations
Cited by 4 Pith papers
-
Gravitational baryogenesis beyond the spectator approximation
Treating the baryogenesis operator as part of the action yields modified Friedmann and Raychaudhuri equations with an effective Planck mass M_eff² = M_Pl² - 2λ ∇_μ J^μ for the vector-density realization of the current.
-
Constraints on Einstein-aether gravity from the precision timing of PSR J1738+0333
Precision timing of PSR J1738+0333 from EPTA and NANOGrav data yields the tightest strong-field constraints on Einstein-aether parameters from any single binary pulsar.
-
Testing General Relativity with Present and Future Astrophysical Observations
A review summarizing modified theories of gravity, their effects on compact objects, existing bounds from astrophysical observations, and the promise of future gravitational wave tests for strong-field gravity.
-
The Confrontation between General Relativity and Experiment
Experiments confirm general relativity to high precision in weak-field and strong-field regimes, with gravitational wave damping matching predictions to better than 0.5 percent.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.