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Updated: Jul 12, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Bound on Lorentz and CPT violating boost effects for the neutron
1Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA.
Physical Review Letters
|December 17, 2004
Summary
This study searched for annual variations in maser frequencies, setting a new limit on Lorentz and CPT violation for neutrons. The findings test spacetime symmetry at an unprecedented level.
Area of Science:
- * Fundamental Physics
- * Particle Physics
- * Quantum Optics
Background:
- * Lorentz and CPT symmetries are fundamental to the Standard Model of particle physics.
- * Violations of these symmetries could indicate new physics beyond the Standard Model.
- * Precise frequency measurements using atomic masers are sensitive probes for detecting such violations.
Purpose of the Study:
- * To search for annual variations in the frequency difference between colocated 129Xe and 3He Zeeman masers.
- * To set stringent limits on boost-dependent Lorentz and CPT violation involving the neutron.
- * To test the fermion sector of the Standard Model Extension (SME) at high energy scales.
Main Methods:
- * Employed a search for an annual modulation in the daily sidereal frequency difference between 129Xe and 3He Zeeman masers.
- * Analyzed maser frequency data to identify potential variations linked to Earth's motion through space.
- * Utilized the Standard Model Extension framework to interpret the results in terms of symmetry violation parameters.
Main Results:
- * Established a stringent limit on boost-dependent Lorentz and CPT violation for the neutron.
- * The observed limit is consistent with no effect at the level of 150 nHz.
- * This result provides the first clean test for the fermion sector of the SME concerning boost transformations.
Conclusions:
- * The experiment places tight constraints on potential violations of fundamental symmetries.
- * The findings contribute to testing the structure of spacetime at energy scales approaching 10(-27) GeV.
- * This work advances the search for new physics beyond the Standard Model using precision maser measurements.
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