Ghost-free braneworld bigravity

@article{Padilla2004GhostfreeBB,
  title={Ghost-free braneworld bigravity},
  author={Antonio Padilla},
  journal={Classical and Quantum Gravity},
  year={2004},
  volume={21},
  pages={2899-2917}
}
  • Antonio Padilla
  • Published 10 February 2004
  • Physics, Geology
  • Classical and Quantum Gravity
We consider a generalization of the DGP model, by adding a second brane with localized curvature, and allowing for a bulk cosmological constant and brane tensions. We study radion and graviton fluctuations in detail, enabling us to check for ghosts and tachyons. By tuning our parameters accordingly, we find bigravity models that are free from ghosts and tachyons. These models will lead to large distance modifications of gravity that could be observable in the near future. 

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