Negative field-space curvature enhances post-inflationary Ricci scalar oscillations and boosts CGPP dark matter number density by up to an order of magnitude relative to flat field-space cases, with nontrivial relic abundance dependence on spectator mass and reheating temperature.
Curvature and isocurvature perturbations from two-field inflation in a slow-roll expansion
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
We calculate the power spectra of primordial curvature and isocurvature perturbations from a general two field inflation model at next-to-leading order correction in a slow-roll expansion. In particular we calculate the spectral indices to second order in slow-roll parameters. We show that the cross-correlation of the curvature and isocurvature perturbations at the time of Hubble-exit during inflation is non-zero at first-order in slow-roll parameters. We apply our results to different classes of inflation, including inflaton and curvaton scenarios. The spectrum of primordial gravitational waves, curvature and isocurvature perturbations obey generalised consistency relations in two-field inflation models. We give the first two consistency relations in an infinite hierarchy.
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First UVLF-based constraints on model-agnostic isocurvature power spectra for CDM, baryon, neutrino, and dark radiation modes yield consistent 95% credible envelopes over k ~ 0.5-10 Mpc^{-1}.
Jordan-frame multi-scalar-tensor gravity admits an Eckart-like first-order thermodynamic description whose heat flux and residual gradient sector are not generically reducible to a single KT-type quantity.
A spectator scalar field with strong portal coupling to the inflaton sources a stochastic gravitational wave background reaching Ω_GW h² ∼ 10^{-11} at frequencies 10^7-10^8 Hz for benchmark parameters σ/λ ≃ 10^4 and T_reh = 2×10^{14} GeV.
citing papers explorer
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Cosmological gravitational particle production in multifield inflation
Negative field-space curvature enhances post-inflationary Ricci scalar oscillations and boosts CGPP dark matter number density by up to an order of magnitude relative to flat field-space cases, with nontrivial relic abundance dependence on spectator mass and reheating temperature.
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New Isocurvature Constraints from JWST UV Luminosity Function
First UVLF-based constraints on model-agnostic isocurvature power spectra for CDM, baryon, neutrino, and dark radiation modes yield consistent 95% credible envelopes over k ~ 0.5-10 Mpc^{-1}.
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First-order thermodynamics of multi-scalar-tensor gravity
Jordan-frame multi-scalar-tensor gravity admits an Eckart-like first-order thermodynamic description whose heat flux and residual gradient sector are not generically reducible to a single KT-type quantity.
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Gravitational Waves from Matter Perturbations of Spectator Scalar Fields
A spectator scalar field with strong portal coupling to the inflaton sources a stochastic gravitational wave background reaching Ω_GW h² ∼ 10^{-11} at frequencies 10^7-10^8 Hz for benchmark parameters σ/λ ≃ 10^4 and T_reh = 2×10^{14} GeV.