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arXiv · 2005.14069

Inflation with non-canonical scalar fields revisited

Smaragda Lola·Andreas Lymperis·Emmanuel N. Saridakis
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Abstract

We revisit inflation with non-canonical scalar fields by applying deformed-steepness exponential potentials. We show that the resulting scenario can lead to inflationary observables, and in particular to scalar spectral index and tensor-to-scalar ratio, in remarkable agreement with observations. Additionally, a significant advantage of the scenario is that the required parameter values, such as the non-canonicality exponent and scale, as well as the potential exponent and scale, do not need to acquire unnatural values and hence can accept a theoretical justification. Hence, we obtain a significant improvement with respect to alternative schemes, and we present distinct correlations between the model parameters that better fit the data, which can be tested in future probes. This combination of observational efficiency and theoretical justification makes the scenario at hand a good candidate for the description of inflation.

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BibTeXRIS

Smaragda Lola, Andreas Lymperis, Emmanuel N. Saridakis. 2020-05-28. Inflation with non-canonical scalar fields revisited. https://doi.org/10.1140/epjc%2Fs10052-021-09516-8

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