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arXiv · hep-ph/9904267

Cosmological Constraints on Theories with Large Extra Dimensions

Lawrence J. Hall·David Smith
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Abstract

In theories with large extra dimensions, constraints from cosmology lead to non-trivial lower bounds on the fundamental scale M_F, corresponding to upper bounds on the radii of the compact extra dimensions. These constraints are especially relevant to the case of two extra dimensions, since only if M_F is 10 TeV or less do deviations from the standard gravitational force law become evident at distances accessible to planned sub-mm gravity experiments. By examining the graviton decay contribution to the cosmic diffuse gamma radiation, we derive, for the case of two extra dimensions, a conservative bound M_F > 110 TeV, corresponding to r_2 < 5.1 times 10^-5 mm, well beyond the reach of these experiments. We also consider the constraint coming from graviton overclosure of the universe and derive an independent bound M_F > 6.5 h^(-1/2) TeV, or r_2 < .015 h mm.

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Lawrence J. Hall, David Smith. 1999-04-23. Cosmological Constraints on Theories with Large Extra Dimensions. https://doi.org/10.1103/physrevd.60.085008

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