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arXiv · 1611.07019

Universality in generalized models of inflation

Pierre Binétruy·Joel Mabillard·Mauro Pieroni
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Abstract

We discuss the cosmological evolution of a scalar field with non standard kinetic term in terms of a Renormalization Group Equation (RGE). In this framework inflation corresponds to the slow evolution in a neighborhood of a fixed point and universality classes for inflationary models naturally arise. Using some examples we show the application of the formalism. The predicted values for the speed of sound $c_s$ and for the amount of non-Gaussianities produced in these models are discussed. In particular, we show that it is possible to introduce models with $c_s^2 \neq 1$ that can be in agreement with present cosmological observations.

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Pierre Binétruy, Joel Mabillard, Mauro Pieroni. 2016-11-22. Universality in generalized models of inflation. https://doi.org/10.1088/1475-7516%2F2017%2F03%2F060

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