Related papers: Resonant features in the stochastic gravitational …
Stochastic inflation, together with the $\Delta N$ formalism, provides a powerful tool for estimating the large-scale behaviour of primordial fluctuations. In this work, we develop a numerical code to capture the non-perturbative statistics…
We derive the perturbation equations for relativistic stars in scalar-tensor theories of gravity and study the corresponding oscillation spectrum. We show that the frequency of the emitted gravitational waves is shifted proportionally to…
We present a new realization of the resonant production of primordial black holes as well as gravitational waves in a two-stage inflation model consisting of a scalar field \phi with an axion-monodromy-like periodic structure in the…
We investigate the gravitational wave background induced by the first order scalar perturbations in the curvaton models. We consider the quadratic and axion-like curvaton potential which can generate the blue-tilted power spectrum of…
Supersymmetric theories, including the minimal supersymmetric standard model, usually contain many scalar fields whose potentials are absent in the exact supersymmetric limit and within the renormalizable level. Since their potentials are…
In canonical scalar field inflation, the Starobinsky model (with a linear potential but discontinuous slope) is remarkable in that though slow-roll is violated, both the power-spectrum and bi-spectrum can be calculated exactly analytically.…
We discuss a scenario in which extra dimensional effects allow a scalar field with a steep potential to play the dual role of the inflaton as well as dark energy (quintessence). The post-inflationary evolution of the universe in this…
One of the fundamental and yet untested predictions of inflationary models is the generation of a very weak cosmic background of gravitational radiation. We investigate the sensitivity required for a space-based gravitational wave laser…
In this paper, we investigate scalar-induced gravitational waves (GWs) generated in the post-inflationary universe to infer new limits on warm inflation. We specifically examine the evolution of primordial GWs by scalar perturbations…
We consider gravitational wave production due to parametric resonance at the end of inflation, or ``preheating''. This leads to large inhomogeneities which source a stochastic background of gravitational waves at scales inside the comoving…
We argue that primordial gravitational waves have a spectral break and its information is quite useful for exploring the early universe. Indeed, such a spectral break can be a fingerprint of the end of inflation, and the amplitude and the…
We consider the 3-pt function (i.e. the bispectrum or non-Gaussianity) for stochastic backgrounds of gravitational waves. We estimate the amplitude of this signal for the primordial inflationary background, gravitational waves generated…
We study how the scalar power spectrum of single-scalar inflation depends functionally on models with features which have been proposed to explain anomalies in the data. We exploit a new formalism based on evolving the norm-squared of the…
We study the properties of the stochastic gravitational wave background (SGWB) produced by domain walls (DWs) during inflation without forming a network. We numerically simulate the DW production caused by a second-order phase transition…
In this paper we calculate the gravitational-wave power-spectra corresponding to different types of transitions between the inflationary regime and the radiation era. We study four cases, where inflation is followed by a stiff matter phase,…
In this work we highlight an important perspective for the complete understanding of the stochastic gravitational background structure. The stochastic gravitational wave background is perhaps the most important current and future tool…
In light of the non-perturbative resonance effects that may occur during inflation, we introduce a parametrization for the power spectrum of the stochastic gravitational wave background (SGWB) characterized by narrow-band amplification. We…
Inflation predicts a stochastic background of gravitational waves over a broad range of frequencies, from those accessible with cosmic microwave background (CMB) measurements, to those accessible directly with gravitational-wave detectors,…
There is a growing expectation that the gravitational wave detectors will start probing the stochastic gravitational wave backgrounds in the following years. We explore the spectral shapes of gravitational waves induced to second order by…
The primordial gravitational waves (\textbf{PGW}) have been generated by inflationary amplification of the primordial (quantum) fluctuations. It is true that they have not been recorded directly so far, but their spectrum can help a lot in…