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Rho Parameter Constraints on Models with Large Compact Dimensions

Prasanta Das·Sreerup Raychaudhuri
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Abstract

In models with large extra dimensions, where quantum gravity effects become strong at the TeV scale, the rho-parameter can receive large contributions from one-loop diagrams involving exchange of multiple graviton and dilaton states. These contributions are computed, taking into account cancellation of spurious infrared divergences, and the (finite) results for d = 5 and 6 are compared with current experimental data. It is shown that 5 large extra dimensions are incompatible with the data and d = 6 is severely constrained.

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Prasanta Das, Sreerup Raychaudhuri. 2000-04-19. Rho Parameter Constraints on Models with Large Compact Dimensions. https://arxiv.org/abs/hep-ph/9908205

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