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Updated: Jul 15, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
New limits on Planck scale Lorentz violation in QED.
T Jacobson1, S Liberati, D Mattingly
1Department of Physics, University of Maryland, College Park, Maryland 20742-4111, USA.
Physical Review Letters
|August 25, 2004
Summary
This study investigates Lorentz symmetry violation (LV) in electrons and photons. New constraints were derived using gamma-ray bursts and synchrotron radiation, improving previous limits.
Area of Science:
- Particle Physics
- Astrophysics
- Cosmology
Background:
- Lorentz symmetry is a cornerstone of modern physics, but theories beyond the Standard Model suggest potential violations.
- Effective Field Theory (EFT) provides a framework to explore potential Lorentz symmetry violations (LV) at high energies.
- Previous constraints on LV parameters for electrons and photons exist but can be improved with new observational data.
Purpose of the Study:
- To constrain possible Lorentz symmetry violation (LV) of order E/M(Planck) for electrons and photons.
- To improve existing bounds on LV parameters using astrophysical observations.
- To investigate differences in LV parameters between electrons and positrons and explore electron helicity decay.
Main Methods:
- Utilizing the polarized MeV emission data from the gamma-ray burst GRB021206.
- Analyzing the absence of vacuum Cherenkov radiation from synchrotron electrons in the Crab Nebula.
- Applying the framework of effective field theory (EFT) to relate LV parameters.
Main Results:
- Improved previous bounds on LV parameters by factors of 10(-10) and 10(-2) using the two distinct astrophysical observations.
- Demonstrated that Lorentz symmetry violation parameters can differ for electrons and positrons.
- Established constraints on electron helicity decay and the impact of EFT-implied relations on prior constraints.
Conclusions:
- Astrophysical observations provide powerful constraints on fundamental physics, including Lorentz symmetry.
- The study significantly tightens limits on potential violations of Lorentz symmetry for charged particles.
- The findings highlight the importance of considering particle-specific LV parameters and their interrelations within EFT.
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