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arXiv · 0808.1262

Trans-Planckian Physics from a Nonlinear Dispersion Relation

S. E. Joras·G. Marozzi
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Abstract

We study a particular nonlinear dispersion relation $ω_p(k_p)$ -- a series expansion in the physical wavenumber $k_p$ -- for modeling first-order corrections in the equation of motion of a test scalar field in a de Sitter spacetime from trans-Planckian physics in cosmology. Using both a numerical approach and a semianalytical one, we show that the WKB approximation previously adopted in the literature should be used with caution, since it holds only when the comoving wavenumber $k\gg aH$. We determine the amplitude and behavior of the corrections on the power spectrum for this test field. Furthermore, we consider also a more realistic model of inflation, the power-law model, using only a numerical approach to determine the corrections on the power spectrum.

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BibTeXRIS

S. E. Joras, G. Marozzi. 2009-01-16. Trans-Planckian Physics from a Nonlinear Dispersion Relation. https://doi.org/10.1103/physrevd.79.023514

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