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arXiv · 0907.3982

Scale Invariance from Modified Dispersion Relations

Yao Lu·Yun-Song Piao
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Abstract

In this paper, inspired by the investigations on the theory of cosmological perturbations in Hořava-Liftshit cosmology, we calculated the spectrum of primordial perturbation leaded by a scalar field with modified dispersion relation ω\sim k^z/a^{p-1}, in which z is the critical exponent and p is generally not equal to z. We discussed that for fixed z, if the spectrum is required to be scale invariant, how should p depend on the background evolution. We concluded that there is always a room of parameters for the generation of scale invariant spectrum.

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Yao Lu, Yun-Song Piao. 2009-07-23. Scale Invariance from Modified Dispersion Relations. https://doi.org/10.1142/s0218271810018074

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