Related papers: Hybrid Quasi-Single Field Inflation
We revisit the hybrid inflation model focusing on the dynamics of the waterfall field in an analytical way. It is shown that inflation may last long enough during the waterfall regime for some parameter regions, confirming the claim of…
We study the quantum fluctuations of scalar fields with a variable effective mass during an inflationary phase. We consider the situation where the effective mass depends on a background scalar field, which evolves during inflation from…
A scalar Higgs field can be repeatedly switched on and off when it couples to a classically oscillating scalar modulus field. The modulus flips the Higgs mass term between stable and tachyonic values. We study a cosmological scenario in…
We study a model of inflation with multiple pseudo-scalar fields coupled to a $U(1)$ gauge field through Chern-Simons interactions. Because of parity violating interactions, one polarization of the gauge field is amplified yielding to…
It has recently been suggested that a strongly coupled phase of inflation may be described holographically in terms of a weakly coupled quantum field theory (QFT). Here, we explore the possibility that the wave function of an inflationary…
In this note we present a simple but exact model of quasi-single field inflation \cite{Chen:2009zp, Chen:2009we}, in which the couplings between perturbations are completely controlled, and for instance can be made constant with any desired…
A model is developed in which the inflaton potential experiences a sudden small change in its second derivative (the effective mass of the inflaton). An exact treatment demonstrates that the resulting density perturbation has a quasi-flat…
We revisit the status of hybrid inflation in the light of Planck and recent BICEP2 results, taking care of possible transient violations of the slow-roll conditions as the field passes from the large field to the vacuum dominated phase. The…
Models of cosmic inflation suggest that our universe underwent an early phase of accelerated expansion, driven by the dynamics of one or more scalar fields. Inflationary models make specific, quantitative predictions for several observable…
We propose a new single field inflation model in which the usual slow-roll inflation is joined to a new period of slow-climb and slow-roll inflation through a short intermediate non-inflationary phase. We then show that primordial curvature…
We develop an integral form for the bispectrum in general single-field inflation whose domain of validity includes models of inflation where the background evolution is not constrained to be slowly varying everywhere. Our integral form…
Cosmological perturbations, originating in the quantum fluctuations of the fields that drive inflation, are observed to be nearly scale invariant at the largest scales. At smaller scales, however, perturbations are not severely constrained…
Attempts at building an unified description of the strong, weak and electromagnetic interactions usually involve several stages of spontaneous symmetry breaking. We consider the effects of such symmetry breaking during an era of primordial…
It has recently been pointed out that a substantial amount of e-folds can occur during the waterfall regime of hybrid inflation. Moreover, Kodama et.al. have derived analytic approximations for the trajectories of the inflaton and of the…
A double hybrid inflationary scenario in non-minimal supergravity which can predict values of the tensor-to-scalar ratio up to about 0.05 is presented. Larger values of this ratio would require unacceptably large running of the scalar…
A new class of particle physics models of inflation based on the phase transition associated with the spontaneous breaking of family symmetry is proposed. The Higgs fields responsible for the breaking of family symmetry, the flavons, are…
We study the observable implications of an incomplete first order phase transition during inflation. In such a phase transition, the nucleated bubbles do not percolate and instead are continuously produced until the onset of reheating. The…
We provide a formula for the scaling behaviour of the inflationary bispectrum in the 'squeezed' limit where one momentum becomes much smaller than the other two. This determines the scaling of the halo bias at low wavenumber and will be an…
We determine the frequency of regions of small-field inflation in the Wigner landscape as an approximation to random supergravities/type IIB flux compactifications. We show that small-field inflation occurs exponentially more often than…
In the framework of chaotic inflation we study the case of a massive scalar field using a semiclassical approach. We derive the energy density fluctuations in the infrared sector generated by matter field and gauge-invariant metric…