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arXiv · 1507.03375

Asymptotically safe inflation from quadratic gravity

Alfio Bonanno·Alessia Platania
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Abstract

Asymptotically Safe theories of gravity have recently received much attention. In this work we discuss a class of inflationary models derived from quantum-gravity modification of quadratic gravity according to the induced scaling around the non-Gaussian fixed point at very high energies. It is argued that the presence of a three dimensional ultraviolet critical surface generates operators of non-integer power of the type $R^{2-θ/2}$ in the effective Lagrangian, where $θ>0$ is a critical exponent. The requirement of a successful inflationary model in agreement with the recent Planck 2015 data puts important constraints on the strenght of this new type of couplings.

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Alfio Bonanno, Alessia Platania. 2015-10-02. Asymptotically safe inflation from quadratic gravity. https://doi.org/10.1016/j.physletb.2015.10.005

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