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arXiv · 0808.0943

Noncommutative Corrections to the Robertson-Walker metric

S. Fabi·B. Harms·A. Stern
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Abstract

Upon applying Chamseddine's noncommutative deformation of gravity we obtain the leading order noncommutative corrections to the Robertson-Walker metric tensor. We get an isotropic inhomogeneous metric tensor for a certain choice of the noncommutativity parameters. Moreover, the singularity of the commutative metric at $t=0$ is replaced by a more involved space-time structure in the noncommutative theory. In a toy model we construct a scenario where there is no singularity at $t=0$ at leading order in the noncommutativity parameter. Although singularities may still be present for nonzero $t$, they need not be the source of all time-like geodesics and the result resembles a bouncing cosmology.

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S. Fabi, B. Harms, A. Stern. 2008-08-07. Noncommutative Corrections to the Robertson-Walker metric. https://doi.org/10.1103/physrevd.78.065037

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