Tests of Lorentz symmetry in the gravitational sector

Understand

Lorentz symmetry is one of the pillars of both General Relativity and the Standard Model of particle physics.

• Motivated by ideas about quantum gravity, unification theories and violations of CPT symmetry, a significant effort has been put the last decades into testing Lorentz symmetry.
• This review focuses on Lorentz symmetry tests performed in the gravitational sector.
• We briefly review the basics of the pure gravitational sector of the Standard-Model Extension (SME) framework, a formalism developed in order to systematically parametrize hypothetical violations of the Lorentz invariance.