Anthropic bound on the cosmological constant.

  title={Anthropic bound on the cosmological constant.},
  journal={Physical review letters},
  volume={59 22},
  • Weinberg
  • Published 27 October 1987
  • Physics
  • Physical review letters
In recent cosmological models, there is an ''anthropic'' upper bound on the cosmological constant ..lambda... It is argued here that in universes that do not recollapse, the only such bound on ..lambda.. is that it should not be so large as to prevent the formation of gravitationally bound states. It turns out that the bound is quite large. A cosmological constant that is within 1 or 2 orders of magnitude of its upper bound would help with the missing-mass and age problems, but may be ruled out… 
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