Multi-scalar-tensor gravity admits an exact covariant thermodynamic interpretation as an imperfect fluid whose heat flux involves a coupling-derived factor χ and a residual gradient sector, yielding multi-field thermal diagnostics and a GR-attractor criterion that is stricter than simple freezing of
Preheating after multifield inflation with nonminimal couplings, III: Dynamical spacetime results
4 Pith papers cite this work. Polarity classification is still indexing.
4
Pith papers citing it
abstract
This paper concludes our semi-analytic study of preheating in inflationary models comprised of multiple scalar fields coupled nonminimally to gravity. Using the covariant framework of paper I in this series, we extend the rigid-spacetime results of paper II by considering both the expansion of the universe during preheating, as well as the effect of the coupled metric perturbations on particle production. The adiabatic and isocurvature perturbations are governed by different effective masses that scale differently with the nonminimal couplings and evolve differently in time. The effective mass for the adiabatic modes is dominated by contributions from the coupled metric perturbations immediately after inflation. The metric perturbations contribute an oscillating tachyonic term that enhances an early period of significant particle production for the adiabatic modes, which ceases on a time-scale governed by the nonminimal couplings $\xi_I$. The effective mass of the isocurvature perturbations, on the other hand, is dominated by contributions from the fields' potential and from the curvature of the field-space manifold (in the Einstein frame), the balance between which shifts on a time-scale governed by $\xi_I$. As in papers I and II, we identify distinct behavior depending on whether the nonminimal couplings are small ($\xi_I \lesssim {\cal O} (1)$), intermediate ($\xi_I \sim {\cal O} (1 - 10)$), or large ($\xi_I \geq 100$).
citation-role summary
background 3
citation-polarity summary
verdicts
UNVERDICTED 4roles
background 3polarities
background 3representative citing papers
Lattice simulations show that the post-inflationary equation of state with trilinear interactions returns to zero after an initial deviation, substantially lowering stochastic gravitational wave amplitudes relative to prior estimates.
In Gauss-Bonnet inflation with monomial potential and coupling, gravitational waves from preheating produce a present-day energy density spectrum consistent with Planck constraints when the coupling strength, equation of state, and efficiency are set to specific values.
Lecture notes providing a generic introduction to reheating after inflation, covering its theoretical, phenomenological, and observational aspects.
citing papers explorer
-
First-order thermodynamics of multi-scalar-tensor gravity
Multi-scalar-tensor gravity admits an exact covariant thermodynamic interpretation as an imperfect fluid whose heat flux involves a coupling-derived factor χ and a residual gradient sector, yielding multi-field thermal diagnostics and a GR-attractor criterion that is stricter than simple freezing of
-
Equation of state during (p)reheating with trilinear interactions
Lattice simulations show that the post-inflationary equation of state with trilinear interactions returns to zero after an initial deviation, substantially lowering stochastic gravitational wave amplitudes relative to prior estimates.
-
Gravitational waves production during preheating within GB gravity with monomial coupling
In Gauss-Bonnet inflation with monomial potential and coupling, gravitational waves from preheating produce a present-day energy density spectrum consistent with Planck constraints when the coupling strength, equation of state, and efficiency are set to specific values.
-
Lectures on Reheating after Inflation
Lecture notes providing a generic introduction to reheating after inflation, covering its theoretical, phenomenological, and observational aspects.