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Large non-gaussianity in axion inflation.
This work reconsiders the cosmological perturbations in axion inflation, consistently accounting for the coupling to gauge fields cΦFF, which is generically present in these models.
Phenomenology of a pseudo-scalar inflaton: naturally large nongaussianity
Many controlled realizations of chaotic inflation employ pseudo-scalar axions. Pseudo-scalars are naturally coupled to gauge fields through cF. In the presence of this coupling, gauge field quanta
Dynamics with infinitely many derivatives: The Initial value problem
Differential equations of infinite order are an increasingly important class of equations in theoretical physics. Such equations are ubiquitous in string field theory and have recently attracted
Gravity waves and non-Gaussian features from particle production in a sector gravitationally coupled to the inflaton
We study the possibility that particle production during inflation could source observable gravity waves on scales relevant for Cosmic Microwave Background experiments. A crucial constraint on such
Gauge Field Production in Axion Inflation: Consequences for Monodromy, non-Gaussianity in the CMB, and Gravitational Waves at Interferometers
Models of inflation based on axions, which owe their popularity to the robustness against UV corrections, have also a very distinct class of signatures. The relevant interactions of the axion are a
Particle Production During Inflation: Observational Constraints and Signatures
In a variety of inflation models the motion of the inflaton may trigger the production of some noninflaton particles during inflation, for example, via parametric resonance or a phase transition.
Signatures of anisotropic sources in the squeezed-limit bispectrum of the cosmic microwave background
The bispectrum of primordial curvature perturbations in the squeezed configuration, in which one wavenumber, k3, is much smaller than the other two, k3 > c0. A cosmic-variance-limited experiment
Observable non-gaussianity from gauge field production in slow roll inflation, and a challenging connection with magnetogenesis
In any realistic particle physics model of inflation, the inflaton can be expected to couple to other fields. We consider a model with a dilaton-like coupling between a U(1) gauge field and a scalar
Catastrophic consequences of kicking the chameleon.
It is demonstrated that quantum particle production can profoundly affect scalar-tensor gravity, a possibility not previously considered, and developed the theory and numerics of particle production in the regime of strong dissipation.
On Features and Nongaussianity from Inflationary Particle Production
Interactions between the inflaton and any additional fields can lead to isolated bursts of particle production during inflation (for example from parametric resonance or a phase transition).