Ekpyrotic universe: Colliding branes and the origin of the hot big bang
Open accessAbstract
We propose a cosmological scenario in which the hot big bang universe is produced by the collision of a brane in the bulk space with a bounding orbifold plane, beginning from an otherwise cold, vacuous, static universe. The model addresses the cosmological horizon, flatness and monopole problems and generates a nearly scale-invariant spectrum of density perturbations without invoking superluminal expansion (inflation). The scenario relies, instead, on physical phenomena that arise naturally in theories based on extra dimensions and branes. As an example, we present our scenario predominantly within the context of heterotic M theory. A prediction that distinguishes this scenario from standard inflationary cosmology is a strongly blue gravitational wave spectrum, which has consequences for microwave background polarization experiments and gravitational wave detectors.
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- Authors
- Khoury, J., Ovrut, B. A., Steinhardt, P. J., & Turok, N.
- Affiliations
- Princeton University (US)
- Venue
- Physical Review D
- Publisher
- American Physical Society (APS)
- Published
- 2001-11-28
- Volume
- 64
- Issue
- 12
- ISSN
- 0556-2821 (ISSN-L)
- 1089-4918
- OpenAlex
- W2029143135
- Cited by
- 1,549
- References
- 4
- Citations by year
- 2026: 36 · 2025: 47 · 2024: 65 · 2023: 40 · 2022: 47 · 2021: 70 · 2020: 65 · 2019: 50 · 2018: 82 · 2017: 50 · 2016: 84 · 2015: 57 · 2014: 71 · 2013: 58 · 2012: 59
- FWCI
- 52.98
- Type
- journal article
- Language
- en
- Open access
- green
- arxiv.org
- Locations
- Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields (publishedVersion)
- arXiv (Cornell University) (submittedVersion)
- CERN Document Server (European Organization for Nuclear Research) (submittedVersion)
- arXiv (Cornell University)
- Topics
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Cosmology and Gravitation Theories
- Physical Sciences › Physics and Astronomy › Nuclear and High Energy Physics › Black Holes and Theoretical Physics
- Physical Sciences › Physics and Astronomy › Statistical and Nonlinear Physics › Noncommutative and Quantum Gravity Theories
- Keywords
- brane collisions, hot big bang, horizon problem, flatness problem, monopole problem, heterotic M-theory, extra dimensions, alternative to inflation
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