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Constraints on torsion from bounds on lorentz violation
V Alan Kostelecký1, Neil Russell, Jay D Tasson
1Physics Department, Indiana University, Bloomington, IN 47405, USA.
Physical Review Letters
|June 4, 2008
Summary
Researchers probed space-time torsion by examining its fermion couplings. New experimental constraints on 19 torsion components were derived, reaching levels of 10(-31) GeV.
Area of Science:
- * Theoretical physics, specifically focusing on extensions to the Standard Model and general relativity.
- * Cosmology and astrophysics, investigating fundamental properties of spacetime.
Background:
- * The Standard Model of particle physics does not incorporate spacetime torsion.
- * Torsion is a feature of Einstein-Cartan theory, an alternative to general relativity, which may play a role in early universe cosmology or quantum gravity.
Purpose of the Study:
- * To establish new experimental constraints on the magnitude of spacetime torsion.
- * To explore the potential for detecting torsion through its interactions with fermions.
Main Methods:
- * Utilizing existing experimental data from searches for violations of Lorentz invariance.
- * Analyzing the theoretical couplings between spacetime torsion and fermionic matter fields.
- * Calculating the sensitivity of experiments to specific components of the torsion tensor.
Main Results:
- * Derived new, stringent constraints on 19 independent components of the spacetime torsion tensor.
- * Established upper limits on torsion components at the order of 10(-31) GeV.
- * Demonstrated that fermion couplings offer a sensitive probe for spacetime torsion.
Conclusions:
- * Experimental searches for Lorentz violation provide powerful constraints on spacetime torsion.
- * The sensitivity achieved significantly advances our understanding of potential deviations from general relativity.
- * Further experimental efforts could refine these constraints and potentially detect spacetime torsion.
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