The role of the gravitational sector in the Lorentz-and CPT-violating standard-model
extension (SME) is studied. A framework is developed for addressing this topic in the context …

The behavior of photons in the presence of Lorentz and CPT violation is studied. Allowing
for operators of arbitrary mass dimension, we classify all gauge-invariant Lorentz-and CPT …

The fate of the Nambu-Goldstone modes arising from spontaneous Lorentz violation is
investigated. Using the vierbein formalism, it is shown that up to 10 Lorentz and …

Because classical Maxwellian electromagnetism has been one of the cornerstones of
physics during the past century, experimental tests of its foundations are always of …

A general formalism is presented for violations of Lorentz and CPT symmetry in the neutrino
sector. The effective Hamiltonian for neutrino propagation in the presence of Lorentz and …

We report on a new test of Lorentz invariance performed by comparing the resonance
frequencies of two orthogonal cryogenic optical resonators subject to Earth's rotation over∼ …

Abstract Space-based experiments offer sensitivity to numerous unmeasured effects
involving Lorentz and CPT violation. We provide a classification of clock sensitivities and …

The static limit of Lorentz-violating electrodynamics in vacuum and in media is investigated.
Features of the general solutions include the need for unconventional boundary conditions …

Lorentz symmetry is a foundational property of modern physics, underlying the standard
model of particles and general relativity. It is anticipated that these two theories are low …

We describe the results of an experiment to test for spacetime anisotropy terms that might
exist from Lorentz violations. The apparatus consists of a pair of cylindrical superconducting …