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Gravitational particle production in braneworld cosmology
1Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara, I-44100, Ferrara, Italy.
Physical Review Letters
|February 1, 2008
Summary
Gravitational particle production in expanding universes is viable in braneworld cosmology. This model allows for faster early universe expansion, enabling abundant particle creation unlike standard cosmology.
Area of Science:
- Cosmology
- Particle Physics
- General Relativity
Background:
- Gravitational particle production is sensitive to the Hubble parameter (H) relative to particle mass.
- Standard cosmology's high Planck mass (M{Pl}) limits this mechanism's relevance.
- Braneworld cosmology offers an alternative framework for early universe dynamics.
Purpose of the Study:
- To investigate gravitational particle production in braneworld cosmology.
- To explore the phenomenological implications of enhanced particle creation in the early universe.
- To discuss the cosmological consequences of these findings.
Main Methods:
- Analysis of particle production in a time-variable metric within an expanding universe model.
- Comparison between standard cosmological models and braneworld scenarios.
- Theoretical exploration of particle creation efficiency based on cosmological parameters.
Main Results:
- Gravitational particle production is efficient when H is not too small compared to particle mass.
- Braneworld cosmology permits a much faster early universe expansion rate.
- This faster expansion facilitates abundant creation of weakly interacting particles.
Conclusions:
- Braneworld cosmology provides a viable mechanism for significant gravitational particle production.
- This mechanism can lead to the abundant creation of many particles in the early universe.
- The cosmological implications of this particle production warrant further investigation.
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