Tachyonic instabilities from post-inflation curvature reorganization via quadratic Gauss-Bonnet coupling produce the observed dark matter relic density across wide mass and scale ranges, backed by lattice simulations and a fitting function.
Canonical reference
Gravitational Particle Production in Oscillating Background and Its Cosmological Implications
Canonical reference. 80% of citing Pith papers cite this work as background.
abstract
We study production of light particles due to oscillation of the Hubble parameter or the scale factor. Any coherently oscillating scalar field, irrespective of its energy fraction in the universe, imprints such an oscillating feature on them. Not only the Einstein gravity but extended gravity models, such as models with non-minimal (derivative) coupling to gravity and $f(R)$ gravity, lead to oscillation of the scale factor. We present a convenient way to estimate the gravitational particle production rate in these circumstances. Cosmological implications of gravitational particle production, such as dark matter/radiation and moduli problem, are discussed. For example, if the theory is described solely by the standard model plus the Peccei-Quinn sector, the Starobinsky $R^2$ inflation may lead to observable amount of axion dark radiation.
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citation-polarity summary
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2026 8representative citing papers
An improved Bogoliubov numerical method computes the full primordial GW spectrum from inflation to reheating and shows that inflaton anharmonicity imprints distinctive features at high frequencies.
For quadratic inflaton potentials Boltzmann and Bogoliubov spectra agree at short wavelengths, but for steeper potentials non-adiabatic transition effects captured only by Bogoliubov are sizable across a broad momentum range.
Lattice QCD computations in thermal effective field theory yield sphaleron rates and axion production rates that deviate from perturbative estimates at high temperatures.
Gravitational scalar production yields reheating-dependent constraints on dark matter scalars, with dilution preserving viability for k<4 low-temperature reheating and factorization in multi-stage cases.
Bose enhancement from a transient condensate of inflaton decay products dramatically increases decay efficiency and amplifies stochastic gravitational wave production to potentially observable levels.
High-frequency primordial gravitational waves extend to higher frequencies due to post-inflation inflaton dynamics, and their detailed spectrum shape can distinguish inflation models.
Gravity-mediated production of scalar and vector dark radiation yields Planck 2018 constraints on reheating temperature T_RH and background equation of state w_Φ, with comparisons to right-handed neutrinos, ALPs, and a generic spin-2 mediator.
citing papers explorer
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Tachyonic gravitational dark matter production after inflation
Tachyonic instabilities from post-inflation curvature reorganization via quadratic Gauss-Bonnet coupling produce the observed dark matter relic density across wide mass and scale ranges, backed by lattice simulations and a fitting function.
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A Unified Bogoliubov Approach to Primordial Gravitational Waves: From Inflation to Reheating
An improved Bogoliubov numerical method computes the full primordial GW spectrum from inflation to reheating and shows that inflaton anharmonicity imprints distinctive features at high frequencies.
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Graviton Production from Inflaton Condensate: Boltzmann vs Bogoliubov
For quadratic inflaton potentials Boltzmann and Bogoliubov spectra agree at short wavelengths, but for steeper potentials non-adiabatic transition effects captured only by Bogoliubov are sizable across a broad momentum range.
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Revisiting the sphaleron and axion production rates in QCD at high temperatures
Lattice QCD computations in thermal effective field theory yield sphaleron rates and axion production rates that deviate from perturbative estimates at high temperatures.
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Gravitational scalar production with a generic reheating scenario
Gravitational scalar production yields reheating-dependent constraints on dark matter scalars, with dilution preserving viability for k<4 low-temperature reheating and factorization in multi-stage cases.
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Probing Bose-enhanced Inflaton Decay with Gravitational Waves
Bose enhancement from a transient condensate of inflaton decay products dramatically increases decay efficiency and amplifies stochastic gravitational wave production to potentially observable levels.
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High Frequency Spectrum of Primordial Gravitational Waves
High-frequency primordial gravitational waves extend to higher frequencies due to post-inflation inflaton dynamics, and their detailed spectrum shape can distinguish inflation models.
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CMB signatures of gravity-mediated dark radiation in $\mathbf{\Delta N_{\rm eff}}$
Gravity-mediated production of scalar and vector dark radiation yields Planck 2018 constraints on reheating temperature T_RH and background equation of state w_Φ, with comparisons to right-handed neutrinos, ALPs, and a generic spin-2 mediator.