An Introduction to Cascading Gravity and Degravitation

@article{Rham2008AnIT,
  title={An Introduction to Cascading Gravity and Degravitation},
  author={Claudia de Rham},
  journal={arXiv: High Energy Physics - Theory},
  year={2008}
}
  • C. D. Rham
  • Published 1 October 2008
  • Physics
  • arXiv: High Energy Physics - Theory
Cascading gravity is an explicit realization of the idea of degravitation, where gravity behaves as a high-pass filter. This could explain why a large cosmological constant does not backreact as much as anticipated from standard General Relativity. The model relies on the presence of at least two infinite extra dimensions while our world is confined on a four-dimensional brane. Gravity is then four-dimensional at short distances and becomes weaker and weaker at larger distances. 

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References

SHOWING 1-10 OF 10 REFERENCES

Softly Massive Gravity

Large-distance modification of gravity may be the mechanism for solving the cosmological constant problem. A simple model of the large-distance modification — four-dimensional (4D) gravity with the

Degravitation of the cosmological constant and graviton width

We study the possibility of decoupling gravity from the vacuum energy. This is effectively equivalent to promoting Newton's constant to a high-pass filter that degravitates sources of characteristic

Renormalization group flows for brane couplings

Field theories in the presence of branes encounter localized divergences that renormalize brane couplings. The sources of these brane-localized divergences are understood as arising either from

Predictive power of strong coupling in theories with large distance modified gravity

We consider theories that modify gravity at cosmological distances, and show that any such theory must exhibit a strong coupling phenomenon, or else it is either inconsistent or is already ruled out

Charting the landscape of modified gravity

We explore brane induced gravity on a 3-brane in six locally flat dimensions. To regulate the short distance singularities in the brane core, we resolve the thin brane by a cylindrical 4-brane, with

The Effective field theory of codimension-two branes

Distributional sources of matter on codimension-two and higher branes are only well-defined as regularized objects. Nevertheless, intuition from effective field theory suggests that the low-energy

Cascading gravity and degravitation

We construct a cascading brane model of gravity in which the behavior of the gravitational force law interpolates from (n+4)-dimensional to (n+3)-dimensional all the way down to 4-dimensional from

Classical Renormalization of Codimension-two Brane Couplings

The curvature on codimension-two and higher branes is not regular for arbitrary matter sources. Nevertheless, the low-energy theory for an observer on such a brane should be well-defined and