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arXiv · 0805.0114

Where does Cosmological Perturbation Theory Break Down?

Cristian Armendariz-Picon·Michele Fontanini·Riccardo Penco·Mark Trodden
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Abstract

We apply the effective field theory approach to the coupled metric-inflaton system, in order to investigate the impact of higher dimension operators on the spectrum of scalar and tensor perturbations in the short-wavelength regime. In both cases, effective corrections at tree-level become important when the Hubble parameter is of the order of the Planck mass, or when the physical wave number of a cosmological perturbation mode approaches the square of the Planck mass divided by the Hubble constant. Thus, the cut-off length below which conventional cosmological perturbation theory does not apply is likely to be much smaller than the Planck length. This has implications for the observability of "trans-Planckian" effects in the spectrum of primordial perturbations.

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Cristian Armendariz-Picon, Michele Fontanini, Riccardo Penco, Mark Trodden. 2008-05-01. Where does Cosmological Perturbation Theory Break Down?. https://doi.org/10.1088/0264-9381%2F26%2F18%2F185002

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