Related papers: Gravity Sector of the SME
Many new linearized coefficients for Lorentz violation are discovered in our recent work on the construction of a generic Lorentz-violating effective field theory in curved spacetime. The new coefficients can be constrained by experiments…
We consider here the possibility of quantum gravity induced violation of Lorentz symmetry (LV). Even if suppressed by the inverse Planck mass such LV can be tested by current experiments and astrophysical observations. We review the…
This proceedings contribution outlines the current structure of the gravity sector of the Standard-Model Extension and summaries recent progress in gravitational wave analysis.
Lorentz symmetry violations can be described by an effective field theory framework that contains both General Relativity and the Standard Model of particle physics called the Standard-Model extension (SME). Recently, post-fit analysis of…
Lorentz symmetry is a fundamental symmetry in the Standard Model (SM) and in General Relativity (GR). This symmetry holds true for all models at low energies. However at energies near the Planck scale, it is conjectured that there may be a…
Small violations of spacetime symmetries have recently been identified as promising Planck-scale signals. This talk reviews how such violations can arise in various approaches to quantum gravity, how the emergent low-energy effects can be…
Lorentz violation is a candidate quantum-gravity signal, and the Standard-Model Extension (SME) is a widely used parametrization of such a violation. In the gravitational SME sector, there is an elusive coefficient for which no effects have…
I present a brief review on the motivation for the study on Lorentz violation and on some of our studies with phenomenological analysis of Lorentz violation effects. I also discuss three effective field theory frameworks for Lorentz…
In recent years, the breakdown of spacetime symmetries has been identified as a promising research field in the context of Planck-scale phenomenology. For example, various theoretical approaches to the quantum-gravity problem are known to…
Analogue models of gravity have provided an experimentally realizable test field for our ideas on quantum field theory in curved spacetimes but they have also inspired the investigation of possible departures from exact Lorentz invariance…
Recently, first limits on putative Lorentz invariance violation coefficients in the pure gravity sector were determined by the reanalysis of short-range gravity experiments. Such experiments search for new physics at sidereal frequencies.…
I review some of the major developments in the theoretical background and experimental uses of binary pulsars to explore local Lorentz invariance in the gravitational sector and its possible violation.
Lorentz and CPT invariance are among the symmetries that can be investigated with ultrahigh precision in subatomic physics. Being spacetime symmetries, Lorentz and CPT invariance can be violated by minuscule amounts in many theoretical…
The one-loop divergences for the scalar field theory with Lorentz and/or CPT breaking terms are obtained in curved space-time. We analyze two separate cases: minimal coupled scalar field with gravity and nonminimal one. For the minimal case…
Some motivations for Lorentz-symmetry tests in the context of quantum-gravity phenomenology are reiterated. The description of the emergent low-energy effects with the Standard-Model Extension (SME) is reviewed. The possibility of…
We motivate the concept of emergent gauge symmetry and discuss ways that this concept can be tested. The key idea is that if a symmetry is emergent, one should look for small violations of this symmetry because the underlying fundamental…
We use the final results from Gravity Probe B to set new upper limits on the gravitational sector of the Standard-Model Extension, including for the first time the coefficient associated with the time-time component of the new field…
Lorentz symmetry is an important concept in modern physics. Precision pulsar timing was used to put tight constraints on the coefficients for Lorentz violation in the pure-gravity sector of the Standard-Model Extension (SME). We extend the…
The violation of spacetime symmetries provides a promising candidate signal for underlying physics, possibly arising at the Planck scale. This talk gives an overview over various aspects in the field, including some mechanisms for Lorentz…
This talk outlines some results for gravitational theories with local Lorentz violation in the context of the Lorentz- and CPT-violating Standard-Model Extension.