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Accelerating Cosmologies and a Phase Transition in M-Theory

Mattias N. R. Wohlfarth
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Abstract

M-theory compactifies on a seven-dimensional time-dependent hyperbolic or flat space to a four-dimensional FLRW cosmology undergoing a period of accelerated expansion in Einstein conformal frame. The strong energy condition is violated by the scalar fields produced in the compactification, as is necessary to evade the no-go theorem for time-independent compactifications. The four-form field strength of eleven-dimensional supergravity smoothly switches on during the period of accelerated expansion in hyperbolic compactifications, whereas in flat compactifications, the three-form potential smoothly changes its sign. For small acceleration times, this behaviour is like a phase transition of the three-form potential, during which the cosmological scale factor approximately doubles.

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Mattias N. R. Wohlfarth. 2003-04-24. Accelerating Cosmologies and a Phase Transition in M-Theory. https://doi.org/10.1016/s0370-2693(03)00609-9

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