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arXiv · 0807.3692

The solution of the cosmological constant problem from the inhomogeneous equation of state - a hint from modified gravity?

Hrvoje Stefancic
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Abstract

The cosmological constant problem is studied in a two component cosmological model. The universe contains a cosmological constant of an arbitrary size and sign and an additional component with an inhomogeneous equation of state. It is shown that, in a proper parameter regime, the expansion of the universe with a large absolute value of the cosmological constant may asymptotically tend to de Sitter space corresponding to a small effective positive cosmological constant. It is argued that such a behavior can be regarded as a solution of the cosmological constant problem in this model. The mechanism behind the relaxation of the cosmological constant is discussed. A connection with modified gravity theories is discussed and an example of a possible realization of the cosmological constant relaxation in f(R) modified gravity is described.

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Hrvoje Stefancic. 2008-11-10. The solution of the cosmological constant problem from the inhomogeneous equation of state - a hint from modified gravity?. https://doi.org/10.1016/j.physletb.2008.10.065

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