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arXiv · 2308.03872

Leading all-loop quantum contribution to the effective potential in the inflationary cosmology

D. I. Kazakov·R. M. Iakhibbaev·D. M. Tolkachev
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Abstract

In this paper, we have constructed quantum effective potentials and used them to study slow-roll inflationary cosmology. We derived the generalised RG equation for the effective potential in the leading logarithmic approximation and applied it to evaluate the potentials of the $T^2$ and $T^4$-models, which are often used in modern models of slow-roll inflation. We found that while the one-loop correction strongly affects the potential, breaking its original symmetry, the contribution of higher loops smoothes the behaviour of the potential. However, unlike the $\phi^4$-case, we found that the effective potentials preserve spontaneous symmetry breaking when summing all the leading corrections. We calculated the spectral indices $n_s$ and $r$ for the effective potentials of both models and found that they are consistent with the observational data for a wide range of parameters of the models.

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D. I. Kazakov, R. M. Iakhibbaev, D. M. Tolkachev. 2023-08-07. Leading all-loop quantum contribution to the effective potential in the inflationary cosmology. https://arxiv.org/abs/2308.03872

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