Separate experiments show no evidence of violation of Lorentz invariance: (Phys.org)—Two teams of researchers working independently of one another have conducted experiments designed to test Lorentz invariance; both report no violations. One of the teams used decades of data from lunar lasing experiments, the other data from experiments conducted over several years using superconducting gravimeters. Both teams have published papers in the journal Physical Review Letters describing their work and their findings. When physicists conduct relativistic experiments that involve physical measurement, their findings should not rely on the orientation or speed of the place in which the experiments take place, according to the standard model of particle physics. This principle is known as Lorentz invariance, and testing it is one of the ways of testing the theory of relativity itself. In this new effort, both research teams have tested the principle with the tightest constraints to date and both offer more accuracy than has been seen in the past. Read more at: https://phys.org/news/2017-11-evidence-violation-lorentz-invariance.html#jCp the two papers: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.119.201102 Lorentz Symmetry Violations from Matter-Gravity Couplings with Lunar Laser Ranging: ABSTRACT The standard-model extension (SME) is an effective field theory framework aiming at parametrizing any violation to the Lorentz symmetry (LS) in all sectors of physics. In this Letter, we report the first direct experimental measurement of SME coefficients performed simultaneously within two sectors of the SME framework using lunar laser ranging observations. We consider the pure gravitational sector and the classical point-mass limit in the matter sector of the minimal SME. We report no deviation from general relativity and put new realistic stringent constraints on LS violations improving up to 3 orders of magnitude previous estimations. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.119.201101 Superconducting-Gravimeter Tests of Local Lorentz Invariance ABSTRACT Superconducting-gravimeter measurements are used to test the local Lorentz invariance of the gravitational interaction and of matter-gravity couplings. The best laboratory sensitivities to date are achieved via a maximum-reach analysis for 13 Lorentz-violating operators, with some improvements exceeding an order of magnitude.
