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Cosmic Acceleration from M Theory on Twisted Spaces

Ishwaree P. Neupane·David L. Wiltshire
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Abstract

In a recent paper [I.P. Neupane and D.L. Wiltshire, Phys. Lett. B 619, 201 (2005).] we have found a new class of accelerating cosmologies arising from a time--dependent compactification of classical supergravity on product spaces that include one or more geometric twists along with non-trivial curved internal spaces. With such effects, a scalar potential can have a local minimum with positive vacuum energy. The existence of such a minimum generically predicts a period of accelerated expansion in the four-dimensional Einstein-conformal frame. Here we extend our knowledge of these cosmological solutions by presenting new examples and discuss the properties of the solutions in a more general setting. We also relate the known (asymptotic) solutions for multi-scalar fields with exponential potentials to the accelerating solutions arising from simple (or twisted) product spaces for internal manifolds.

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BibTeXRIS

Ishwaree P. Neupane, David L. Wiltshire. 2005-10-16. Cosmic Acceleration from M Theory on Twisted Spaces. https://doi.org/10.1103/physrevd.72.083509

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