Related papers: Gravitational Waves from Kinetic Preheating
We develop a new approach to gravitational waves in which the Einstein equations are governed by the cosmological constant which is related to the existence of a manifold which is closed. We study an example in which the matter Lagrangian…
We provide a simple transfer function that determines the effect of an early matter dominated era on the gravitational wave background and show that a large class of compactifications of superstring theory might be tested by observations of…
In this letter we study the generation of gravitational waves during inflation from a 5D vacuum theory of gravity. Within this formalism, on an effective 4D de Sitter background, we recover the typical results obtained with 4D inflationary…
Scalar-induced gravitational waves (SIGWs) provide a powerful probe of inflationary dynamics on scales far smaller than those accessible to the cosmic microwave background and large-scale structure. In scenarios with a transient…
Primordial gravitational waves are a crucial prediction of inflation theory, and their detection through their imprints on the cosmic microwave background is actively being pursued. However, these attempts have not yet been successful. In…
For the first time, the possibility of generation of thermal gravitational waves from warm inflation is investigated with cosmic microwave background. Gravitons produced from the quantum fluctuations during warm inflation are found to carry…
We compute numerically the reheating temperature due to the gravitational production of conformally coupled superheavy particles during the phase transition from the end of inflation to the beginning of kination in two different…
Part A of this article is devoted to the general investigation of the gravitational-wave emission by post-Newtonian sources. We show how the radiation field far from the source, as well as its near-zone inner gravitational field, can (in…
We discuss the production of gravity waves from the fragmentation of a supersymmetric condensate in the early universe. Supersymmetry predicts the existence of flat directions in the potential. At the end of inflation, the scalar fields…
We study the production of gravitational waves during oscillations of the inflaton around the minimum of a cuspy potential after inflation. We find that a cusp in the potential can trigger copious oscillon formation, which sources a…
We study (p)reheating in alpha-attractor T-models of inflation, taking into account both scalar fields present in these models: the inflaton and the spectator. The two-field model has a negative field-space curvature which, at the end of…
We investigate scalar-induced stochastic gravitational waves from adiabatic curvature perturbations sourced by a spectator field via the modulated reheating mechanism. We consider a spectator scalar with Higgs-like couplings and inflaton…
We study the scalar induced gravitational wave (GW) background in inflation with gravitationally enhanced friction (GEF). The GEF mechanism, which is realized by assuming a nonminimal derivative coupling between the inflaton field and…
A fundamental prediction of inflation is a nearly scale-invariant spectrum of gravitational wave. The features of such a signal provide extremely important information about the physics of the early universe. In this paper, we focus on…
Gravitational waves emitted by black hole binary inspiral and mergers enable unprecedented strong-field tests of gravity, requiring accurate theoretical modelling of the expected signals in extensions of General Relativity. In this paper we…
We systematically investigate the preheating behavior of single field inflation with an oscillon-supporting potential. We compute the properties of the emitted gravitational waves (GWs) and the number density and characteristics of the…
The scalar and tensor fluctuations generated during inflation can be correlated, if arising from the same underlying mechanism. In this paper we investigate such correlation in the model of axion inflation, where the rolling inflaton…
In warm inflation, dissipation due to the interactions of the inflaton field to other light degrees of freedom leads naturally to the enhancement of the primordial spectrum during the last 10-20 efolds of inflation. We study this effect in…
We study preheating in plateau inflation in the Palatini formulation of general relativity, in a special case that resembles Higgs inflation. It was previously shown that the oscillating inflaton field returns to the plateau repeatedly in…
We consider a model in which a pseudo-scalar field $\sigma$ rolls for some e-folds during inflation, sourcing one helicity of a gauge field. These fields are only gravitationally coupled to the inflaton, and therefore produce scalar and…