The variance of the CMB temperature gradient: a new signature of a multiply connected Universe

  title={The variance of the CMB temperature gradient: a new signature of a multiply connected Universe},
  author={Ralf Aurich and Thomas Buchert and Martin J. France and Frank Steiner},
  journal={Classical and Quantum Gravity},
In this work we investigate the standard deviation of the cosmic microwave background (CMB) temperature gradient field as a signature for a multiply connected nature of the Universe. CMB simulations of a spatially infinite Universe model within the paradigm of the standard cosmological model present non-zero two-point correlations at any angular scale. This is in contradiction with the extreme suppression of correlations at scales above 60° in the observed CMB maps. Universe models with… 
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