相关论文: Gravitational Waves from Particles Produced from B…
We study the effect of density perturbations on the process of first-order phase transitions and gravitational wave production in the early Universe. We are mainly interested in how the distribution of nucleated bubbles is affected by…
The low frequency part of the gravitational wave spectrum generated by local physics, such as a phase transition or parametric resonance, is largely fixed by causality, offering a clean window into the early Universe. In this work, this low…
Some fraction of compact binaries that merge within a Hubble time may have formed from two massive stars in isolation. For this isolated-binary formation channel, binaries need to survive two supernova (SN) explosions in addition to…
Spectra of stochastic gravitational waves (GW) generated in cosmological first-order phase transitions are computed within strongly correlated theories with a dual holographic description. The theories are mostly used as models of dark…
The reheating of the universe after hybrid inflation proceeds through the nucleation and subsequent collision of large concentrations of energy density in the form of bubble-like structures moving at relativistic speeds. This generates a…
We discuss spectra of gravitational waves which are originated by the strongly first order phase transition at the electroweak symmetry breaking, which is required for a successful scenario of electroweak baryogenesis. Such spectra are…
The stochastic gravitational wave (GW) background provides a fascinating window to the physics of the very early universe. Beyond the nearly scale-invariant primordial GW spectrum produced during inflation, a spectrum with a much richer…
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…
In this article, we investigate the stochastic gravitational waves (GWs) spectrum, resulting from the emission of gravitons through bremsstrahlung, in the decay of particles produced by Hawking radiation. Although particle decays inevitably…
Gravitational waves (GW) can constitute a unique probe of the primordial universe. In many cases, the characteristic frequency of the emitted GW is directly related to the energy scale at which the GW source is operating in the early…
We search for a first-order phase transition (PT) gravitational wave (GW) signal from Advanced LIGO and Advanced Virgo's first three observing runs. Due to the large theoretical uncertainties, four GW energy spectral shapes from bubble and…
This paper explores the physics of second-order gravitational waves (GWs) induced by scalar-tensor perturbation interactions in the radiation-dominated Universe. We investigate the distinctive signatures of these GWs and their detectability…
Gravitational waves were copiously produced in the early Universe whenever the processes taking place were sufficiently violent. The spectra of several of these gravitational wave backgrounds on subhorizon scales have been extensively…
Causal soliton formation (e.g. oscillons, Q-balls) in the primordial Universe is expected to give rise to a universal gravitational wave (GW) background, at frequencies smaller than scales of nonlinearity. We show that modifications of the…
We investigate how the production of gravitational waves (GWs) is affected by the GW velocity $(c_T)$ during preheating after inflation. For instance, we simulate the production of GWs after $\lambda\phi^4$ chaotic inflation, and find that…
The bubble wall velocity in an electroweak first order phase transition is a key quantity both for electroweak baryogenesis and for the production of a stochastic background of gravitational waves that may be probed in the future through…
Gravitational wave (GW) oscillations occur whenever there are additional tensor modes interacting with the perturbations of the metric coupled to matter. These extra modes can arise from new spin-2 fields (as in e.g. bigravity theories) or…
Networks of cosmic domain walls can form in the early Universe as a consequence of the spontaneous breaking of discrete symmetries. We study the production of a cosmological background of gravitational waves (GWs) from such networks, when…
We study the imprints of new ultralight particles on the gravitational-wave signals emitted by binary black holes. Superradiant instabilities may create large clouds of scalar or vector fields around rotating black holes. The presence of a…
At the present moment, there is an unresolved problem in the physics of cosmic rays. The problem concerns the origin of the ultrahigh energy cosmic rays. One of the possible mechanisms of the particle's birth with such energy is bound to…