Accelerated expansion from ghost-free bigravity: a statistical analysis with improved generality

  title={Accelerated expansion from ghost-free bigravity: a statistical analysis with improved generality},
  author={Yashar Akrami and Tomi S. Koivisto and Marit Sandstad},
  journal={Journal of High Energy Physics},
A bstractWe study the background cosmology of the ghost-free, bimetric theory of gravity. We perform an extensive statistical analysis of the model using both frequentist and Bayesian frameworks and employ the constraints on the expansion history of the Universe from the observations of supernovae, the cosmic microwave background and the large scale structure to estimate the model’s parameters and test the goodness of the fits. We explore the parameter space of the model with nested sampling to… 

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