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Accelerating Cosmologies from Exponential Potentials

Ishwaree P. Neupane
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Abstract

An exponential potential of the form $V\sim \exp(-2c ϕ/M_p)$ arising from the hyperbolic or flux compactification of higher-dimensional theories is of interest for getting short periods of accelerated cosmological expansions. Using a similar potential but derived for the combined case of hyperbolic-flux compactification, we study the four-dimensional flat (and open) FLRW cosmologies and give analytic (and numerical) solutions with exponential behavior of scale factors. We show that, for the M-theory motivated potentials, the cosmic acceleration of the universe can be eternal if the spatial curvature of the 4d spacetime is negative, while the acceleration is only transient for a spatially flat universe. We also comment on the size of the internal space and its associated geometric bounds on massive Kaluza-Klein excitations.

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Ishwaree P. Neupane. 2004-08-30. Accelerating Cosmologies from Exponential Potentials. https://doi.org/10.1088/0264-9381%2F21%2F18%2F007

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