Inflation with Massive Spin-2 Ghosts

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.

19 pages, 1 figure, v2

References in corpus (11)

• Making Sense of Non-Hermitian Hamiltonians
• BICEP / Keck XIII: Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season
• No-ghost theorem for the fourth-order derivative Pais-Uhlenbeck oscillator model
• Metastability in Quadratic Gravity
• Weyl Current, Scale-Invariant Inflation and Planck Scale Generation
• Embedding inflation into the Standard Model - more evidence for classical scale invariance
• The Ostrogradsky instability can be overcome by quantum physics
• Dimensional Transmutation in Gravity and Cosmology
• Predictions of quantum gravity in inflationary cosmology: effects of the Weyl-squared term
• Scale-invariant inflation with one-loop quantum corrections
• Multi-field effects in a simple extension of $R^2$ inflation