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Anthropic distribution for cosmological constant and primordial density perturbations

DOI:10.1016/j.physletb.2004.08.061
Authors:
Michael L. Graesser
Michael L. Graesser
Michael L. Graesser
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Stephen D.H. Hsu
Stephen D.H. Hsu
Stephen D.H. Hsu
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Alejandro Jenkins at University of Costa Rica
Alejandro Jenkins
Mark B. Wise
Mark B. Wise
Mark B. Wise
  • This person is not on ResearchGate, or hasn't claimed this research yet.
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Abstract

The Anthropic Principle has been proposed as an explanation for the observed value of the cosmological constant. Here we revisit this proposal by allowing for variation between universes in the amplitude of the scale-invariant primordial cosmological density perturbations. We derive a priori probability distributions for this amplitude from toy inflationary models in which the parameter of the inflaton potential is smoothly distributed over possible universes. We find that for such probability distributions, the likelihood that we live in a typical, anthropically-allowed universe is generally quite small.
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... Putting everything together we find t 0 ∼ t G ∼ t Λ and the coincidence problem seems to be resolved. It is clear that some assumptions must be made about the origin and evolution of intelligent life and these have drawn some criticism [143,144]. It is typically argued that, although anthropic constraints can select values of the cosmological constant which are close to the observed value, these values necessarily carry large uncertainties due to the lack of understanding of the conditions required for intelligent life to appear. ...
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