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Updated: Jul 17, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
A cyclic model of the universe
Paul J Steinhardt1, Neil Turok
1Joseph Henry Laboratories, Princeton University, Princeton, NJ 08544, USA. steinh@princeton.edu
Science (New York, N.Y.)
|April 27, 2002
Summary
This cosmological model proposes a universe with endless cycles of "bang" and "crunch." Each cycle features slow expansion and contraction, providing conditions for the next cosmic epoch.
Area of Science:
- Cosmology
- Astrophysics
- Theoretical Physics
Background:
- Current cosmological models grapple with explaining the universe's origin and evolution.
- The concept of a singular beginning and end is challenged by cyclic universe theories.
Purpose of the Study:
- To propose a novel cosmological model featuring a cyclic universe.
- To explain cosmic homogeneity, flatness, and energy through a bang-crunch sequence.
Main Methods:
- Theoretical modeling of cosmic epochs.
- Analysis of conditions during the transition between cosmic cycles.
Main Results:
- The proposed model describes an endless sequence of cosmic bangs and crunches.
- Finite temperature and density are maintained at the bang-crunch transition.
- Each cycle includes slow accelerated expansion followed by contraction.
Conclusions:
- The cyclic model offers an alternative to inflationary cosmology.
- The bang-crunch sequence naturally generates the required homogeneity, flatness, and energy for subsequent cycles.
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