相关论文: Hybrid inflation and gravitational waves from acci…
In many models of inflation, the period of accelerated expansion ends with preheating, a highly non-thermal phase of evolution during which the inflaton pumps energy into a specific set of momentum modes of field(s) to which it is coupled.…
Stochastic gravitational waves can be induced from the primordial curvature perturbations generated during inflation, through scalar-tensor mode coupling at the second order of cosmological perturbation theory. Here we discuss a model of…
A model is presented in which a single scalar field is responsible for both primordial inflation at early times and then dark energy at late times. This field is coupled to a second scalar field which becomes unstable and starts to…
Extensions of the Standard Model typically contain ``flaton fields" defined as fields with large vacuum expectation values and almost flat potentials where scalar self-coupling is small or vanishes at tree level. Such potentials have been…
A spontaneously broken global discrete symmetry may have pseudo Goldstone modes associated with the spontaneous breaking of the approximate continuous symmetry of the low dimension terms in the Lagrangian. These provide natural candidates…
A field kinetic coupling with the Einstein tensor leads to a gravitationally enhanced friction during inflation, by which even steep potentials with theoretically natural model parameters can drive cosmic acceleration. In the presence of…
We show how successful supersymmetric hybrid inflation is realized in realistic models where the resolution of the minimal supersymmetric standard model mu problem is intimately linked with axion physics. The scalar fields that accompany…
We propose a new framework for multi-field inflation in which a nearly constant potential energy is maintained during inflation before decreasing rapidly, in a manner analogous to a classical top spinning upright for a long time before…
A direct detection of primordial gravitational waves is the ultimate probe for any inflation model. While current CMB bounds predict the generic scale-invariant gravitational wave spectrum from slow-roll inflation to be below the reach of…
The detection of a primordial stochastic gravitational wave background has the potential to reveal unprecedented insights into the early universe, and possibly into the dynamics of inflation. Generically, UV-complete inflationary models…
We investigate the inhomogeneous inflation, in which the space exponentially expands with inhomogeneities, and its cosmological perturbations. The inhomogeneous inflation is realized by introducing scalar fields with spacelike gradients…
An important prediction of inflation is the production of a primordial stochastic gravitational wave background. Observing this background is challenging due to the weakness of the signal and the simultaneous presence of an astrophysical…
Cosmological inflation gives a natural answer for a variety of cosmological questions, including the horizon problem, the flatness problem, and others. However, inflation yields new questions relating to the flatness of the inflaton…
A pseudoscalar inflaton $\varphi$, coupled to the topological charge density $F\tilde{F}$ of a non-Abelian sector, can decay to gauge bosons ($\varphi\to g g $), which may thermalize rapidly. The friction felt by $\varphi$ is then increased…
We consider the construction of inverted hybrid inflation models in which the vacuum energy during inflation is at the TeV scale, and the inflaton couples to the Higgs field. Such models are of interest in the context of some recently…
We discuss the hybrid inflation model where the inflaton field is nonminimally coupled to gravity. In the Jordan frame, the potential contains $\phi^4$ term as well as terms in the original hybrid inflation model. In our model, inflation…
The non-supersymmetric and supersymmetric versions of hybrid inflation are summarized. It is emphasized that supersymmetric hybrid inflation (with its extensions) is an extremely "natural" inflationary scenario since it does not require…
The motion of a pseudo-scalar field $X$ during inflation naturally induces a significant amplification of the gauge fields to which it is coupled. The amplified gauge fields can source characteristic scalar and tensor primordial…
After inflation, a period of preheating may have produced a stochastic background of high frequency gravitational waves (GWs) that would persist until today. The nature of the inflaton's coupling to Standard Model or other fields is…
We argue that gravitational wave contribution to the cosmic microwave background anisotropy at angular scale $\sim 10^0$ may exceed 50% for some models of hybrid inflation producing standard cosmology with the density perturbation slope $n…