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Full-Text Articles in Physical Sciences and Mathematics
Testing Velocity-Dependent Cpt-Violating Gravitational Forces With Radio Pulsars, Lijing Shao, Quentin G. Bailey
Testing Velocity-Dependent Cpt-Violating Gravitational Forces With Radio Pulsars, Lijing Shao, Quentin G. Bailey
Publications
In the spirit of effective field theory, the standard-model extension (SME) provides a comprehensive framework to systematically probe the possibility of Lorentz/CPT violation. In the pure gravity sector, operators with mass dimension larger than 4, while in general being advantageous to short-range experiments, are hard to investigate with systems of astronomical size. However, there is exception if the leading-order effects are CPT-violating and velocity-dependent. Here we study the lowest-order operators in the pure gravity sector that violate the CPT symmetry with carefully chosen relativistic binary pulsar systems. Applying the existing analytical results to the dynamics of a binary orbit, we …
Constraints On Violations Of Lorentz Symmetry From Gravity Probe B, James M. Overduin, Ryan D. Everett, Quentin G. Bailey
Constraints On Violations Of Lorentz Symmetry From Gravity Probe B, James M. Overduin, Ryan D. Everett, Quentin G. Bailey
Publications
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 responsible for inducing local Lorentz violation in the theory.
Local Lorentz-Symmetry Breaking And Gravity, Q. G. Bailey
Local Lorentz-Symmetry Breaking And Gravity, Q. G. Bailey
Publications
The lagrangian-based Standard-Model Extension framework offers a broad description of possible gravitational effects from local Lorentz violation. In this talk, I review the status of the theoretical and phenomenological work in this area. The extension of previous results in linearized gravity to the nonlinear regime is discussed.
Gravity Couplings In The Standard-Model Extension, Quentin G. Bailey
Gravity Couplings In The Standard-Model Extension, Quentin G. Bailey
Publications
The Standard-Model Extension (SME) is an action-based expansion describing general Lorentz violation for known matter and fields, including gravity. In this talk, I will discuss the Lorentz-violating gravity couplings in the SME. Toy models that match the SME expansion, including vector and two-tensor models, are reviewed. Finally I discuss the status of experiments and observations probing gravity coefficients for Lorentz violation.