Measure problem in cosmology

  title={Measure problem in cosmology},
  author={G. W. Gibbons and Neil Turok},
  journal={Physical Review D},
The Hamiltonian structure of general relativity provides a natural canonical measure on the space of all classical universes, i.e., the multiverse. We review this construction and show how one can visualize the measure in terms of a 'magnetic flux' of solutions through phase space. Previous studies identified a divergence in the measure, which we observe to be due to the dilatation invariance of flat Friedmann-Lemaitre-Robertson-Walker universes. We show that the divergence is removed if we… 

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