Relaxing the TCC Bound on Inflationary Cosmology?

Abstract

We demonstrate that the strict upper bounds on the energy scale of inflation and on the tensor-to-scalar ratio can be somewhat relaxed if we assume that - after an initial period of slow rolling when scales probed today in CMB experiments exit the Hubble radius - the equation of state of the background changes to correspond to an almost marginally accelerating universe. Constructing an actual model in which this happens appears, however, to be unnatural.

5 pages, no figures; a few minor algebra errors corrected, matches with the published version (European Journal of Physics C)

References in corpus (1)

• On the Geometry of the String Landscape and the Swampland

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