Einstein-aether theory, violation of Lorentz invariance, and metric-affine gravity

There is evidence that Newton and Einstein's theories of gravity cannot explain the dynamics of a universe made up solely of baryons and radiation. To be able to understand the properties of galaxies, clusters of galaxies and the universe on the whole it has become commonplace to invoke the presence of dark matter. An alternative approach is to modify the gravitational field equations to accommodate observations. We propose a new class of gravitational theories in which we add a new degree of freedom, the Aether, in the form of a vector field that is coupled covariantly, but non-minimally, with the space-time metric. We explore the Newtonian and non-Newtonian limits, discuss the conditions for these theories to be consistent and explore their effect on cosmology.

show abstract

“…The gravitational field equations for this theory, obtained by varying g αβ (see [17] but also [18]) are…”

Section: The Theorymentioning

confidence: 99%

Modifying gravity with the aether: An alternative to dark matter

2007

View full text Add to dashboard Cite

show abstract

“…[16,17,18,19,20,21,22,23] and references therein. These theories can be thought of as low energy effective field theory descriptions of local Lorentz violation (LV) possibly arising from quantum gravitational physics at energies near the Planck scale.…”

Section: Introductionmentioning

confidence: 99%

Erratum: Neutron stars in Einstein-Aether theory [Phys. Rev. D76, 042003 (2007)]

Eling¹,

Jacobson²,

Miller³

2009

Phys. Rev. D

View full text Add to dashboard Cite

As current and future experiments probe strong gravitational regimes around neutron stars and black holes, it is desirable to have theoretically sound alternatives to General Relativity against which to test observations. Here we study the consequences of one such generalization, Einstein-aether theory, for the properties of non-rotating neutron stars. This theory has a parameter range that satisfies all current weak-field tests. We find that within this range it leads to lower maximum neutron star masses, as well as larger surface redshifts at a particular mass, for a given nuclear equation of state. For non-rotating black holes and neutron stars, the innermost stable circular orbit is only slightly modified in this theory.

show abstract

“…10 , see also Heinicke et al 27 , demonstrating that the key is to look for further integrability conditions. Especially the first Bianchi identity (8) turns out to be helpful in answering this question.…”

Section: Master Equation For Solving the Field Equations Algebraicallymentioning

confidence: 99%

Rotating Black Holes in Metric-Affine Gravity

Baekler

Hehl

2006

Int. J. Mod. Phys. D

Self Cite

View full text Add to dashboard Cite

Within the framework of metric-affine gravity (MAG, metric and an independent linear connection constitute spacetime), we find, for a specific gravitational Lagrangian and by using prolongation techniques, a stationary axially symmetric exact solution of the vacuum field equations. This black hole solution embodies a Kerr-deSitter metric and the post-Riemannian structures of torsion and nonmetricity. The solution is characterized by mass, angular momentum, and shear charge, the latter of which is a measure for violating Lorentz invariance. file Baekler/Magaxi13.tex

show abstract

Einstein-aether theory, violation of Lorentz invariance, and metric-affine gravity

Cited by 86 publications

References 75 publications

Modifying gravity with the aether: An alternative to dark matter

Modifying gravity with the aether: An alternative to dark matter

Erratum: Neutron stars in Einstein-Aether theory [Phys. Rev. D76, 042003 (2007)]

Rotating Black Holes in Metric-Affine Gravity

Contact Info

Product

Resources

About