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arXiv · 1810.06332

Testing velocity-dependent CPT-violating gravitational forces with radio pulsars

Lijing Shao·Quentin G. Bailey
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Abstract

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 put constraints on various coefficients for Lorentz/CPT violation with mass dimension 5. These constraints, being derived from the post-Newtonian dynamics for the first time, are complementary to those obtained from the kinematics in the propagation of gravitational waves.

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BibTeXRIS

Lijing Shao, Quentin G. Bailey. 2018-10-15. Testing velocity-dependent CPT-violating gravitational forces with radio pulsars. https://doi.org/10.1103/physrevd.98.084049

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