Why anthropic reasoning cannot predict Lambda.

  title={Why anthropic reasoning cannot predict Lambda.},
  author={Glenn D Starkman and R Trotta},
  journal={Physical review letters},
  volume={97 20},
We revisit anthropic arguments purporting to explain the measured value of the cosmological constant. We argue that different ways of assigning probabilities to candidate universes lead to totally different anthropic predictions. As an explicit example, we show that weighting different universes by the total number of possible observations leads to an extremely small probability for observing a value of Lambda equal to or greater than what we now measure. We conclude that anthropic reasoning… 
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