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Constraining axion inflation with gravitational waves from preheating
We study gravitational wave production from gauge preheating in a variety of inflationary models, detailing its dependence on both the energy scale and the shape of the potential. In this work, we show that preheating into Abelian gauge fields generically leads to a large gravitational wave background that contributes significantly to the effective number of relativistic degrees of freedom in the early universe, $N_{\text{eff}}$. We demonstrate that the efficiency of gravitational wave production is correlated with the tensor-to-scalar ratio, $\textit{r}$. In particular, we show that efficient gauge preheating in models whose tensor-to-scalar ratio would be detected by next-generation cosmic microwave background experiments ($\textit{r}$ ≳ 10 –3 ) will be either detected through its contribution to $N_{\text{eff}}$ or ruled out. Furthermore, we show that bounds on $N_{\text{eff}}$ provide the most sensitive probe of the possible axial coupling of the inflaton to gauge fields regardless of the potential.
Stochastic evolution of scalar fields with continuous symmetries during inflation
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Power spectrum of density perturbations in chain inflation
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Starobinksy inflation, gravitational contact terms, and the induced Brout-Englert-Higgs boson mass
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Unified model for inflation, pseudo-Goldstone dark matter, neutrino mass, and baryogenesis
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Radiative plateau inflation with conformal invariance: Dynamical generation of electroweak and seesaw scales
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Reheating consistency condition on the classically conformal U ( 1 ) B – L Higgs inflation model
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Bayesian reasoning in eternal inflation: A solution to the measure problem
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Standard model Higgs inflation supplemented by minimal dark matter
Renormalization group analysis with the present measurements of the top quark mass m t = 172.69 ± 0.30 GeV [1] indicates that the Standard Model (SM) Higgs potential becomes unstable at energy scales ∼ 10 10 GeV . This may be interpreted as hinting at new particles at high energy. The minimal extension of the SM that can avoid this instability while leaving the SM Higgs as the sole scalar particle of the theory is obtained by adding suitable fermions to the SM. These fermions are good dark matter candidates and the model is known as the minimal dark matter model. We revisit the inflationary scenario based on the minimal dark matter model, taking into account updated parameter constraints and recent understanding of reheating dynamics. We explore the model with different values of the right-handed neutrino mass and find that the cosmological prediction is insensitive to such details. We obtained a spectral index of the cosmic microwave background n s = 0.9672 and a tensor-to-scalar ratio r = 0.0031 as a robust prediction of this scenario. Published by the American Physical Society 2024
Phase transition during inflation and the gravitational wave signal at pulsar timing arrays
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Full-shape analysis with simulation-based priors: Constraints on single field inflation from BOSS
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Natural inflation with exponentially small tensor-to-scalar ratio
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Affleck-Dine Leptogenesis from Higgs Inflation
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Inflation, proton decay, and Higgs-portal dark matter in $$SO(10) \times U(1)_\psi $$
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