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Lorentz Symmetry Violations from Matter-Gravity Couplings with Lunar Laser Ranging.
A Bourgoin1, C Le Poncin-Lafitte2, A Hees3
1Dipartimento di Ingegneria Industriale, University of Bologna, via fontanelle 40, Forlì, Italy.
Physical Review Letters
|December 9, 2017
Summary
This study presents the first direct experimental measurement of Standard-Model Extension (SME) coefficients using lunar laser ranging. No violations to Lorentz symmetry (LS) were detected, setting stringent new constraints on LS.
Area of Science:
- Theoretical Physics
- Astrophysics
- Experimental Physics
Background:
- The Standard-Model Extension (SME) framework parametrizes potential violations of Lorentz symmetry (LS) across all physics sectors.
- Previous constraints on LS violations were primarily theoretical or indirect experimental results.
- Lunar laser ranging offers a unique observational platform for testing fundamental physics.
Purpose of the Study:
- To perform the first direct experimental measurement of SME coefficients.
- To simultaneously probe the gravitational and matter sectors of the minimal SME.
- To test for violations of Lorentz symmetry using astrophysical observations.
Main Methods:
- Utilized lunar laser ranging observations to gather experimental data.
- Analyzed data within the framework of the Standard-Model Extension (SME).
- Focused on the pure gravitational sector and the classical point-mass limit in the matter sector.
Main Results:
- No deviation from General Relativity was observed.
- New stringent constraints on Lorentz symmetry (LS) violations were established.
- Constraints were improved by up to 3 orders of magnitude compared to previous estimations.
Conclusions:
- The study provides the tightest experimental constraints to date on Lorentz symmetry violations.
- Lunar laser ranging is a powerful tool for testing fundamental physics theories.
- Current observations are consistent with the principles of General Relativity.
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