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Brane gas-driven bulk expansion as a precursor stage to brane inflation
Natalia Shuhmaher1, Robert Brandenberger
1Department of Physics, McGill University, 3600 University Street, Montréal, Québec H3A 2T8, Canada.
Physical Review Letters
|May 23, 2006
Summary
This study introduces a novel method for achieving slow-roll inflation in higher-dimensional string and M-theory models. It utilizes orbifolded extra dimensions and a hot dense brane gas to generate cosmic inflation and subsequent reheating.
Area of Science:
- Cosmology
- String Theory
- Higher-Dimensional Physics
Background:
- Cosmic inflation is a key component of the standard Big Bang model.
- Higher-dimensional theories, such as string theory, offer potential frameworks for understanding fundamental physics.
- Generating slow-roll inflation within these complex models presents significant theoretical challenges.
Purpose of the Study:
- To propose a new mechanism for realizing slow-roll inflation in higher-dimensional models.
- To investigate the role of orbifold compactification and brane gas cosmology.
- To explain the stabilization of extra dimensions and the reheating process.
Main Methods:
- Modeling inflation within higher-dimensional spacetime.
- Utilizing orbifolded extra spatial dimensions.
- Simulating initial conditions with a hot dense bulk brane gas.
- Analyzing the effects of inter-plane potentials and string-scale physics.
Main Results:
- A period of slow-roll inflation for the observable three dimensions is achieved.
- The contraction of bulk dimensions is sufficiently slow to support inflation.
- Radion modes are stabilized by string effects at the string scale.
- Reheating occurs through the conversion of bulk branes into radiation.
Conclusions:
- The proposed model provides a viable pathway to slow-roll inflation in string/M-theory inspired scenarios.
- Orbifolding and brane gas dynamics are crucial for generating and sustaining inflation.
- The mechanism naturally incorporates stabilization of extra dimensions and reheating.
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