2004/07/31 by Michael L. Graesser, Stephen D. H. Hsu, Alejandro Jenkins +1
Physics and Astronomy · #hep-th #astro-ph #gr-qc
paper · pdf · doi:10.1016/j.physletb.2004.08.061
published as Phys.Lett. B600 (2004) 15-21 · 12 pages, 2 tables. v3: Replaced to match published version (minor corrections of form)
arxiv created 2004/09/29 · arxiv updated 2009/12/01
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.