Related papers: Stochastic gravitational background from inflation…
If there was a first order phase transition in the early universe, there should be an associated stochastic background of gravitational waves. In this paper, we point out that the characteristic frequency of the spectrum due to phase…
Phase transitions during inflation can generate a stochastic gravitational-wave background that probes primordial physics. We study the detectability and parameter reconstruction of such a signal with a space-based gravitational-wave…
We discuss a new source of gravitational waves (GWs) from first-order phase transitions. The collisions of bubbles of the new phase can efficiently produce particles that couple to the background field undergoing the transition, thereby…
We investigate the properties of gravitational waves generated by heating induced phase transitions in warm inflation. In this scenario, the heating phase of inflation followed by subsequent cosmological cooling can trigger two associated…
We reexamine the production of gravitational waves by bubble collisions during a first-order phase transition. The spectrum of the gravitational radiation is determined by numerical simulations using the "envelope approximation". We find…
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…
First-order phase transitions in the early Universe are a well-motivated source of gravitational waves (GWs). In this Letter, we identify a previously overlooked GW production mechanism: gravitational transition radiation, arising from…
In the present thesis, the author reviews the physics of cosmological first-order phase transitions that may have occured shortly after the Big Bang. Such transitions proceed via the nucleation and expansion of true vacuum bubbles and give…
We propose a novel mechanism where a first-order phase transition modulates the decay rate of a massive field. This modulation, even if the scalar field has negligible energy density, subsequently generates an observable stochastic…
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…
Preheating and other particle production phenomena in the early Universe can give rise to high- energy out-of-equilibrium fermions with an anisotropic stress. We develop a formalism to calculate the spectrum of gravitational waves due to…
It is currently believed that the Standard Model is an effective low energy theory which in principle may contain higher dimensional non-renormalizable operators. These operators may modify the standard model Higgs potential in many ways,…
We study the properties of the gravitational wave (GW) signals produced by first order phase transitions during the inflation era. We show that the power spectrum of the GW oscillates with its wave number. This signal can be observed…
During a strongly first-order phase transition gravitational waves are produced by bubble collisions and turbulent plasma motion. We analyze the relevant characteristics of the electroweak phase transition in the nMSSM to determine the…
The primordial spectrum of fluctuations may present a large peak as a result of enhancing features during inflation. This may include, but is not limited to, bumps in the inflaton's potential, phases of ultra-slow-roll or turns in…
Particle phase transitions in the early universe including electroweak and grand unification ones are well-studied subjects. We point out that there are new possible particle phase transitions around inflation. Those new inflationary…
In double-field inflation, which exploits two scalar fields, one of the fields rolls slowly during inflation whereas the other field is trapped in a meta-stable vacuum. The nucleation rate from the false vacuum to the true one becomes…
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…
An injection of energy into the early Universe on a given characteristic length scale will result in turbulent motions of the primordial plasma. We calculate the stochastic background of gravitational radiation arising from a period of…
Grishchuk has shown that the stochastic background of gravitational waves produced by an inflationary phase in the early Universe has an unusual property: it is not a stationary Gaussian random process. Due to squeezing, the phases of the…