Distinguishing modified gravity from dark energy

  title={Distinguishing modified gravity from dark energy},
  author={Edmund Bertschinger and Phillip Zukin},
  journal={Physical Review D},
The acceleration of the Universe can be explained either through dark energy or through the modification of gravity on large scales. In this paper we investigate modified gravity models and compare their observable predictions with dark energy models. Modifications of general relativity are expected to be scale independent on superhorizon scales and scale dependent on subhorizon scales. For scale-independent modifications, utilizing the conservation of the curvature scalar and a parametrized… 

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  • Physics
    Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
  • 2011
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