Related papers: Relic Cosmological Vector Fields and Inflationary …
A strong variable gravitational field of the very early Universe inevitably generates relic gravitational waves by amplifying their zero-point quantum oscillations. We begin our discussion by contrasting the concepts of relic gravitational…
We discuss the effects of cosmic phase transition on the spectrum of primordial gravitational waves generated during inflation. The energy density of the scalar condensation responsible for the phase transition may become sizable at the…
Cosmological vector fields are central to many early-Universe phenomena, including inflationary dynamics, primordial magnetogenesis, and dark-matter scenarios. However, constructing models able to generate cosmological magnetic fields while…
We investigate the impact of the post-inflationary thermal histories on the cosmic graviton spectrum caused by the inflationary variation of their refractive index. Depending on the frequency band, the spectral energy distribution can be…
The next generation of gravitational wave detectors holds out the prospect of detecting a stochastic gravitational background generated in the very early universe. In this article, we review the various cosmological processes which can lead…
If during inflation the inflaton couples to a "fossil" field, some new scalar, vector, or tensor field, it typically induces a scalar-scalar-fossil bispectrum. Even if the fossil field leaves no direct physical trace after inflation, it…
The accelerating expansion of the Universe at the present stage is a process that will change the spectrum of relic gravitational waves. Here we present a numerical calculation for the power spectrum of relic gravitational waves in the…
In the inflation models, the relic gravitational waves (RGW) generated in the inflation stage, and evolved in the Universe until now. In the different cosmological evolution models, one can get different gravitational waves power spectrum.…
A cosmological gauge field with isotropic stress-energy introduces parity violation into the behavior of gravitational waves. We show that a primordial spectrum of inflationary gravitational waves develops a preferred handedness, left- or…
A large class of string-cosmology backgrounds leads to a spectrum of relic stochastic gravitational waves, strongly tilted towards high frequencies, and characterized by two basic parameters of the cosmological model. We estimate the…
The spectra of relic gravitational waves produced as a result of cosmological expansion of the inflationary models are derived in Brans-Dicke theory of gravity.The time dependence of the very early Hubble parameter and matter energy density…
Upcoming searches for the stochastic background of inflationary gravitational waves (GWs) offer the exciting possibility to probe the evolution of our Universe prior to Big Bang nucleosynthesis. In this spirit, we explore the sensitivity of…
In this paper we explore the impact of an era -right after reheating- dominated by mini black holes and radiation on the spectrum of the relic gravitational waves. This era may lower the spectrum several orders of magnitude.
The longitudinal components of massive vector fields generated during inflation constitute a well-motivated dark matter candidate, with interesting phenomenological implications. During the epoch of radiation domination following inflation,…
Gravitational waves signatures from dynamical scalar field configurations provide a compelling observational window on the early universe. Here we identify intriguing connections between dark matter and scalars fields that emit…
A characteristic spectrum of relic gravitational radiation is produced by a period of ``stringy inflation" in the early universe. This spectrum is unusual, because the energy-density rises rapidly with frequency. We show that correlation…
After a review of a traditional analysis, it is shown a variation of a more recent treatment on the spectrum of relic gravitational waves (GWs). Then, a connection between the two different treatments will be analysed. Such a connection…
We investigate the production of gravitational waves during preheating after inflation in the common case of field potentials that are asymmetric around the minimum. In particular, we study the impact of oscillons, comparatively long lived…
We study the most general effects of relic vector fields on the inflationary background and density perturbations. Such effects are observable if the number of inflationary e-folds is close to the minimum requirement to solve the horizon…
We propose to uncover the signature of a stringy era in the primordial Universe by searching for a prominent peak in the relic graviton spectrum. This feature, which in our specific model terminates an $\omega^3$ increase and initiates an…