THE RETURN OF THE PHOENIX UNIVERSE

@article{Lehners2009THERO,
  title={THE RETURN OF THE PHOENIX UNIVERSE},
  author={Jean-Luc Lehners and Paul J. Steinhardt and Neil Turok},
  journal={International Journal of Modern Physics D},
  year={2009},
  volume={18},
  pages={2231-2235}
}
Georges Lemaitre introduced the term "phoenix universe" to describe an oscillatory cosmology with alternating periods of gravitational collapse and expansion. This model is ruled out observationally, because it requires a supercritical mass density and cannot accommodate dark energy. However, a new cyclic theory of the universe has been proposed that evades these problems. In a recent elaboration of this picture, almost the entire universe observed today is fated to become entrapped inside… 
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References

SHOWING 1-10 OF 16 REFERENCES
Dark energy and the return of the phoenix universe
In cyclic universe models based on a single scalar field (e.g., the radion determining the distance between branes in M theory), virtually the entire Universe makes it through the ekpyrotic smoothing
The Ekpyrotic universe: Colliding branes and the origin of the hot big bang
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,
Generating Ekpyrotic Curvature Perturbations Before the Big Bang
We analyze a general mechanism for producing a nearly scale-invariant spectrum of cosmological curvature perturbations during a contracting phase preceding a big bang, which can be entirely described
Cosmic Evolution in a Cyclic Universe
Based on concepts drawn from the ekpyrotic scenario and M theory, we elaborate our recent proposal of a cyclic model of the universe. In this model, the universe undergoes an endless sequence of
A Cyclic Model of the Universe
TLDR
A cosmological model in which the universe undergoes an endless sequence of cosmic epochs that begin with a "bang" and end in a “crunch" is proposed, which produces the homogeneity, flatness, and energy needed to begin the next cycle.
Cosmic gravitational-wave background in a cyclic universe
Inflation predicts a primordial gravitational wave spectrum that is slightly ``red.'' In this Brief Report, we compute both the amplitude and spectral form of the primordial tensor spectrum predicted
Why the Cosmological Constant Is Small and Positive
TLDR
This paper shows that a cyclic model of the universe can naturally incorporate a dynamical mechanism that automatically relaxes the value of the cosmological constant, including contributions to the vacuum density at all energy scales.
FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE * OBSERVATIONS: COSMOLOGICAL INTERPRETATION
The Wilkinson Microwave Anisotropy Probe (WMAP) 5-year data provide stringent limits on deviations from the minimal, six-parameter Λ cold dark matter model. We report these limits and use them to
Annales Soc
  • Sci. Brux. Ser. I A 53, 51
  • 1933
Science 296
  • 1436 (2002); Phys. Rev. D 65, 126003
  • 2002
...
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