Related papers: Gravitational Atoms
We review sources of high-frequency gravitational waves, summarizing our current understanding of emission mechanisms, expected amplitudes and event rates. The most promising sources are gravitational collapse (formation of black holes or…
Gravitons radiated from light, evaporating black holes contribute to the stochastic background of gravitational waves. The spectrum of such emission depends on both the mass and the spin of the black holes, as well as on the redshifting…
This review is focused on tests of Einstein's theory of general relativity with gravitational waves that are detectable by ground-based interferometers and pulsar-timing experiments. Einstein's theory has been greatly constrained in the…
A rich galaxy cluster showing strong resemblance with the observed ones is simulated. Cold dark matter spectrum, Gaussian statistics, flat universe, and two components -- baryonic gas plus dark matter particles -- are considered. We have…
The existence of gravitational radiation is a natural prediction of any relativistic description of the gravitational interaction. In this chapter, we focus on gravitational waves, as predicted by Einstein's general theory of relativity.…
In our recently proposed quantum theory of gravity, the universe is made of `atoms' of space-time-matter (STM). Planck scale foam is composed of STM atoms with Planck length as their associated Compton wave-length. The quantum dispersion…
Gravitational waves (GWs) at ultra-low frequencies (${\lesssim 100\,\mathrm{nHz}}$) are key to understanding the assembly and evolution of astrophysical black hole (BH) binaries with masses $\sim 10^{6}-10^{9}\,M_\odot$ at low redshifts.…
"If one could ever prove the existence of gravitational waves, the processes responsible for their generation would probably be much more curious and interesting than even the waves themselves." (Gustav Mie, 1868 - 1957) The discovery of…
In many particle physics models, domain wall can form during the phase transition process after discrete symmetry breaking. We study the scenario within a complex singlet extended Standard Model framework, where a strongly first order phase…
In this manuscript we review the theoretical foundations of gravitational waves in the framework of Albert Einstein's theory of general relativity. Following Einstein's early efforts we first derive the linearised Einstein field equations…
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…
We study gravitational waves generated during the inflationary epoch in presence of a decaying cosmological parameter on a 5D geometrical background which is Riemann flat. Two examples are considered, one with a constant cosmological…
We investigate the sources of the Hubble-induced mass for a flat direction in supersymmetric theories and show that the sign of the Hubble-induced mass generally changes just after the end of inflation. This implies that global cosmic…
An enigmatic prediction of Einstein's general theory of relativity is gravitational waves. With the observed decay in the orbit of the Hulse-Taylor binary pulsar agreeing within a fraction of a percent with the theoretically computed decay…
Gravitational waves in cylindrically symmetric Einstein gravity are described by an effective energy tensor with the same form as that of a massless Klein- Gordon field, in terms of a gravitational potential generalizing the Newtonian…
The ultrahigh-frequency (above 10 kHz) gravitational waves (GW) window provides a unique opportunity to detect primordial GWs, free from astrophysical foregrounds that dominate lower frequencies. A stochastic GW background in this range is…
We study the production, spectrum and detectability of gravitational waves in models of the early Universe where first order phase transitions occur during inflation. We consider all relevant sources. The self-consistency of the scenario…
In the framework of Einstein-scalar-Gauss-Bonnet (EsGB) gravity, we systematically study gravitational waves (GWs), first produced by remote compact astrophysical sources and then propagating through the flat homogeneous and isotropic…
In this note we will first argue that there is evidence in supporting the view that de Broglie waves have a gravitational origin. In view of the extreme weakness of the gravitational field, however, this seems to be an unlikely proposition.…
Gravitational waves (GWs) are fluctuations in the fabric of spacetime predicted by Einstein's theory of general relativity. Using a collection of millisecond pulsars as high-precision clocks, the nanohertz band of this radiation is likely…