Computation of Gravitational Particle Production Using Adiabatic Invariants

Abstract

Analytic and numerical techniques are presented for computing gravitational production of scalar particles in the limit that the inflaton mass is much larger than the Hubble expansion rate at the end of inflation. These techniques rely upon adiabatic invariants and time modeling of a typical inflaton field which has slow and fast time variation components. A faster computation time for numerical integration is achieved via subtraction of slowly varying components that are ultimately exponentially suppressed. The fast oscillatory remnant results in production of scalar particles with a mass larger than the inflationary Hubble expansion rate through a mechanism analogous to perturbative particle scattering. An improved effective Boltzmann collision equation description of this particle production mechanism is developed. This model allows computation of the spectrum using only adiabatic invariants, avoiding the need to explicitly solve the inflaton equations of motion.

37 pages, 5 figures

References in corpus (9)

• Gravitational Production of Dark Matter during Reheating
• Gravitational Effects on Inflaton Decay
• On Thermal Gravitational Contribution to Particle Production and Dark Matter
• More hilltop inflation models
• Gravitational production of nearly thermal fermionic Dark Matter
• Irruption of massive particle species during inflation
• Hunting super-heavy dark matter with ultra-high energy photons
• Electroweak Vacuum Metastability and Low-scale Inflation
• Electroweak-Symmetric Dark Monopoles from Preheating

Cited by in corpus (5)

• Snowmass2021 Cosmic Frontier White Paper: Ultraheavy particle dark matter
• Cosmological gravitational particle production of massive spin-2 particles
• Scalar field couplings to quadratic curvature and decay into gravitons
• Quantum interference in gravitational particle production
• Entropy Production in the Inflationary Epoch Using the Gouy-Stodola Theorem