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arXiv · 2211.01546

On the superstring-inspired quantum correction to the Starobinsky model of inflation

Sergei V. Ketov·Ekaterina O. Pozdeeva·Sergey Yu. Vernov
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Abstract

Superstring/M-theory is the theory of quantum gravity that can provide the UV-completion to viable inflation models. We modify the Starobinsky inflation model by adding the Bel-Robinson tensor $T^{\mu\nu\lambda\rho}$ squared term proposed as the leading quantum correction inspired by superstring theory. The $(R+\frac{1}{6m^2}R^2 -\frac{\beta}{8m^6}T^2)$ model under consideration has two parameters: the inflaton mass $m$ and the string-inspired positive parameter $\beta$. We derive the equations of motion in the Friedmann-Lemaitre-Robertson-Walker universe and investigate its solutions. We find the physical bounds on the value of the parameter $\beta$ by demanding the absence of ghosts and consistency of the derived inflationary observables with the measurements of the cosmic microwave background radiation.

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Sergei V. Ketov, Ekaterina O. Pozdeeva, Sergey Yu. Vernov. 2022-11-03. On the superstring-inspired quantum correction to the Starobinsky model of inflation. https://doi.org/10.1088/1475-7516%2F2022%2F12%2F032

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