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Quantum gravity corrections to neutrino propagation
Alfaro1, Morales-Tecotl, Urrutia
1Facultad de Fisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22, Chile.
Physical Review Letters
|October 6, 2000
Summary
Loop quantum gravity predicts spacetime structure corrections affecting spin-1/2 particle propagation. This leads to observable time delays in high-energy neutrino bursts traveling cosmological distances.
Area of Science:
- Theoretical Physics
- Quantum Gravity
- Particle Physics
Background:
- Loop quantum gravity offers a framework for quantizing spacetime.
- Understanding quantum gravity effects on fundamental fields is crucial.
- High-energy astrophysical phenomena like gamma-ray bursts provide natural laboratories.
Purpose of the Study:
- To investigate the impact of loop quantum gravity on massive spin-1/2 fields.
- To analyze potential observable consequences for neutrino propagation over cosmological distances.
- To explore corrections to field propagation arising from spacetime discreteness.
Main Methods:
- Studied massive spin-1/2 fields within the loop quantum gravity framework.
- Approximated a spin-1/2 field in flat spacetime at scales much larger than Planck length.
- Analyzed corrections to field propagation due to spacetime's discrete structure.
Main Results:
- Identified a dominant, helicity-independent correction leading to time delays in neutrino bursts.
- Calculated the time delay to be of the order of 10^4 seconds for neutrinos of approximately 10^5 GeV.
- Found a next-order correction similar to the Gambini and Pullin effect for photons, and a dependence on oscillation length.
Conclusions:
- The discrete nature of spacetime in loop quantum gravity induces observable effects on particle propagation.
- Time delays in high-energy neutrino bursts offer a potential avenue for testing quantum gravity.
- These findings have implications for understanding neutrino oscillations and fundamental physics.
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