Related papers: Gravitational wave sources: reflections and echoes
"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…
Alternative theories of gravity predict the presence of massive scalar, vector, and tensor gravitational wave modes in addition to the standard massless spin~2 graviton of general relativity. The deflection and frequency shift effects on…
A gravitational wave stochastic background of astrophysical origin may have resulted from the superposition of a large number of unresolved sources since the beginning of stellar activity. Its detection would put very strong constrains on…
Gravitational waves can probe the existence of planetary-mass primordial black holes. Considering a mass range of $[10^{-7}-10^{-2}]M_\odot$, inspiraling primordial black holes could emit either continuous gravitational waves,…
Astrophysical sources of high frequency gravitational radiation are considered in association with a new interest to very sensitive HFGW receivers required for the laboratory GW Hertz experiment. A special attention is paid to the…
Massive black hole binaries (MBHBs) are unavoidable outcomes of the hierarchical structure formation process, and according to the theory of general relativity are expected to be the loudest gravitational wave (GW) sources in the Universe.…
Nonlinear gravitational wave memory is a surprise of theoretical physics. Whereas it is understood that a gravitational wave induces oscillatory squeezing and stretching motion in a collection of freely-falling test masses, it is unexpected…
We investigate a generic source of stochastic gravitational wave background due to the parametric resonance of oscillating scalar fields in the early Universe. By systematically analyzing benchmark models through lattice simulations and…
In this white paper, we discuss the prospects for characterizing and identifying dark matter using gravitational waves, covering a wide range of dark matter candidate types and signals. We argue that present and upcoming gravitational wave…
Gravitational-wave detectors can search for yet-undiscovered ultralight bosons, including those conjectured to solve problems in particle physics, high-energy theory and cosmology. Ground-based instruments could probe boson masses between…
We study gravitational absorption effects using effective on-shell scattering amplitudes. We develop an in-in probability-based framework involving plane- and partial-wave coherent states for the incoming wave to describe the interaction of…
Gravitational waves from binary coalescences provide one of the cleanest signatures of the nature of compact objects. It has been recently argued that the post-merger ringdown waveform of exotic ultracompact objects is initially identical…
Various theories of dark matter predict distinctive astrophysical signatures in gravitational-wave sources that could be observed by ground- and space-based laser interferometers. Different candidates-including axions, dark photons,…
The existence of scalar fields can be probed by observations of stochastic gravitational waves. Scalar fields mediate attractive forces, usually stronger than gravity, on the length scales shorter than their Compton wavelengths, which can…
We have numerically investigated close scattering processes of two black holes (BHs). Our careful analysis shows for the first time a non-merging ringdown gravitational wave coming from dynamical tidal deformations of individual BHs during…
The light deflection under a strong gravitational field, referred to as strong gravitational lensing, provides a powerful probe of spacetime geometry. Besides, laboratory analogue models are employed to study the effects of curved spacetime…
After a short review of prominent properties of gravitational waves and the newly born gravitational astronomy, we focus on theoretical aspects. Analytic approximation methods in general relativity have played a crucial role in the recent…
The first generation of gravitational wave interferometric detectors has taken data at, or close to, their design sensitivity. This data has been searched for a broad range of gravitational wave signatures. An overview of gravitational wave…
Is gravity quantum mechanical? If so, we argue that nonlinear effects in black hole ringdowns - notably second harmonic generation - generates gravitational waves in non-classical states. While quantum features of these states such as…
The gravitational waves emitted by massive black hole binaries can be affected by a variety of environmental effects, which, if detected, could inform astrophysics and cosmology. We here study how gravitational waves emitted by black holes…