Likely Values of the Cosmological Constant

  title={Likely Values of the Cosmological Constant},
  author={Hugo Martel and Paul R. Shapiro and Steven Weinberg},
  journal={The Astrophysical Journal},
  pages={29 - 40}
In theories in which the cosmological constant takes a variety of values in different "subuniverses," the probability distribution of its observed values is conditioned by the requirement that there be someone to measure it. This probability is proportional to the fraction of matter that is destined to condense out of the background into mass concentrations large enough to form observers. We calculate this "collapsed fraction" with a simple, pressure-free, spherically symmetric, nonlinear model… 

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