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Magnetic field production during preheating at the electroweak scale
Andrés Díaz-Gil1, Juan García-Bellido, Margarita García Pérez
1Instituto de Física Teórica UAM/CSIC, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
Physical Review Letters
|July 23, 2008
Summary
This study explores magnetic field generation during hybrid inflation preheating. It confirms Vachaspati
Area of Science:
- Cosmology
- Particle Physics
- Astrophysics
Background:
- Cosmic inflation is a key theory explaining the early universe's rapid expansion.
- The electroweak scale is a significant energy scale in particle physics.
- The origin of large-scale magnetic fields in the universe remains an open question.
Purpose of the Study:
- To investigate the generation of magnetic fields during the preheating phase of hybrid inflation.
- To examine the nonperturbative and out-of-equilibrium processes involved in magnetic field generation.
- To compare theoretical predictions with observational constraints on cosmic magnetic fields.
Main Methods:
- Simulating magnetic field generation within a hybrid inflation model.
- Analyzing the helicity and correlation length of generated magnetic fields.
- Comparing the magnitude of generated fields with electroweak energy density.
Main Results:
- Confirmed the Vachaspati prediction for nonperturbative, out-of-equilibrium magnetic field generation with nontrivial helicity.
- Observed linear growth in the magnitude and correlation length of helical magnetic fields during preheating.
- Found field magnitudes (rho_{B}/rho_{EW} ~ 10{-2}) consistent with seeds for observed galactic microgauss fields.
Conclusions:
- The preheating phase in hybrid inflation provides a viable mechanism for generating primordial magnetic fields.
- These generated helical magnetic fields possess properties consistent with those needed to explain observed cosmic magnetic fields.
- The study supports the possibility of these fields originating from electroweak-scale preheating phenomena.
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