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arXiv · 2207.14329

Inflation with Massive Spin-2 Ghosts

Jisuke Kubo·Jeffrey Kuntz·Jonas Rezacek·Philipp Saake
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Abstract

We consider a generic model of quadratic gravity coupled to a single scalar and investigate the effects of gravitational degrees of freedom on inflationary parameters. We find that quantum corrections arising from the massive spin-2 ghost generate significant contributions to the effective inflationary potential and allow for a realization of the spontaneous breakdown of global scale invariance without the need for additional scalar fields. We compute inflationary parameters, compare the resulting predictions to well-known inflationary models, and find that they fit well within the Planck and BICEP/Keck collaboration's constraints on inflation.

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Jisuke Kubo, Jeffrey Kuntz, Jonas Rezacek, Philipp Saake. 2022-07-28. Inflation with Massive Spin-2 Ghosts. https://doi.org/10.1088/1475-7516%2F2022%2F11%2F049

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