Is Cosmic Speed-Up Due to New Gravitational Physics?

@article{Carroll2003IsCS,
  title={Is Cosmic Speed-Up Due to New Gravitational Physics?},
  author={S. Carroll and Vikram Duvvuri and Mark Trodden and Michael S. Turner},
  journal={Physical Review D},
  year={2003},
  volume={70},
  pages={043528}
}
We show that cosmic acceleration can arise due to very tiny corrections to the usual gravitational action of general relativity, of the form ${R}^{\ensuremath{-}n}$ with $ng0.$ This model eliminates the need for a nonzero cosmological constant or any other form of dark energy, attributing a purely gravitational origin to the acceleration of the universe. 

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