Related papers: What Do We Know About Lorentz Invariance?
Generalized uncertainty principles (GUP) and, independently, Lorentz symmetry violations are two common features in many candidate theories of quantum gravity. Despite that, the overlap between both has received limited attention so far. In…
CPT invariance in neutrino physics has attracted attention after the revival of the hypothetical idea that neutrino and antineutrino might have nonequal masses ($m_{\bar\nu} \neq m_{\nu}$) when realizing neutrino oscillations as a new…
A review is presented of some recent Lorentz and CPT tests in atomic and particle systems where the predominant interactions are described by quantum electrodynamics. A theoretical framework extending QED in the context of the standard…
Lorentz symmetry is a fundamental space-time symmetry underlying the Standard Model of particle physics and gravity. However, unified theories, such as string theory, allow for violation of this symmetry. Thus, the discovery of Lorentz…
Clock-comparison experiments conducted in space can provide access to many unmeasured coefficients for Lorentz and CPT violation. The orbital configuration of a satellite platform and the relatively large velocities attainable in a…
If textbook Lorentz invariance is actually a property of the equations describing a sector of the excitations of vacuum above some critical distance scale, several sectors of matter with different critical speeds in vacuum can coexist and…
This article reviews recent developments in tests of fundamental physics using atoms and molecules, including the subjects of parity violation, searches for permanent electric dipole moments, tests of the CPT theorem and Lorentz symmetry,…
This work presents a model for testing Lorentz and CPT symmetry using rovibrational transitions within the electronic ground state of the molecular hydrogen ion (H$^+_2$). The model is based on the Standard-Model Extension (SME) and…
Motivated by ideas about quantum gravity, a tremendous amount of effort over the past decade has gone into testing Lorentz invariance in various regimes. This review summarizes both the theoretical frameworks for tests of Lorentz invariance…
Tests of CPT and Lorentz symmetry using neutral-meson oscillations are studied within a formalism that allows for indirect CPT and T violation of arbitrary size and is independent of phase conventions. The analysis is particularly…
Effective gravitational field theories with background fields break local Lorentz symmetry and diffeomorphism invariance. Examples include Chern-Simons gravity, massive gravity, and the Standard-Model Extension (SME). The physical…
The interest of part of the quantum-gravity community in the possibility of Planck-scale-deformed Lorentz symmetry is also fueled by the opportunities for testing the relevant scenarios with analyses, from a signal-propagation perspective,…
We show that the standard Lorentz transformations admit an invariant mass (length) scale, such as the Planck scale. In other words, the frame independence of such scale is built-in within those transformations, and one does not need to…
Investigations on possible violation of Lorentz invariance have been widely pursued in the last decades, both from theoretical and experimental sides. A comprehensive framework to formulate the problem is the standard model extension (SME)…
We provide a brief overview into recent tests of gravity, focusing on its foundational spacetime symmetries. In particular, we work with an agnostic, effective field-theory framework, named the Standard-Model Extension, that allows for…
Although Lorentz symmetry has been tested at low energy with extremely good accuracy, its validity at very high energy is much less well established. If Lorentz symmetry violation (LSV) is energy-dependent (e.g. $\propto E^2$), it can be of…
The ongoing experimental efforts in the high energy and high precision communities keep providing evidence for CPT, a fundamental symmetry holding in any local Lorentz invariant theory. We suggest possible interconnections between different…
A review of recent theoretical work investigating tests of Lorentz and CPT symmetry in atomic and particle systems is presented. A variety of tests in matter and antimatter are discussed, including measurements of anomalous magnetic moments…
In the past decade the phenomenology of quantum gravity has been dominated by the search of violations of Lorentz invariance. However, there are very serious arguments that led us to assume that this invariance is a symmetry in Nature. This…
We consider the mechanism of spontaneous symmetry breaking of a bulk vector field to study signatures of bulk dimensions invisible to the standard model confined to the brane. By assigning a non-vanishing vacuum expectation value to the…