Related papers: Gravitational wave memory in $\Lambda$CDM cosmolog…
We examine a simple example of gravitational wave memory due to the decay of a point particle into two point particles. In the case where one of the decay products is null, there are two types of memory: a null memory due to the null…
We study gravitational lensing when plasma surrounds the lens. An extra deflection angle is induced by the plasma in addition to the deflection generated by gravity. An inhomogeneous plasma distribution generates a greater effect than a…
Similar to light, gravitational waves (GWs) can be lensed. Such lensing phenomena can magnify the waves, create multiple images observable as repeated events, and superpose several waveforms together, inducing potentially discernible…
Gravitational wave (GW) astronomy opens a new venue to explore the universe. Future observatories such as LISA, the Laser Interferometer Space Antenna, are expected to observe previously undetectable fundamental physics effects in signals…
The memory effect is known to introduce a permanent displacement in the gravitational wave (GW) detectors after the passage of a GW signal. While the linear memory adheres to the source properties, the non-linear memory is a secondary…
A passing gravitational wave causes a deflection in the apparent astrometric positions of distant stars. The effect of the speed of the gravitational wave on this astrometric shift is discussed. A stochastic background of gravitational…
The propagation of gravitational waves is explored in the cosmological context. It is explicitly demonstrated that the propagation of gravitational waves could be influenced by the medium. It is shown that in the thermal radiation, the…
In this talk I review how a non-zero cosmological constant $\Lambda$ affects the propagation of gravitational waves and their detection in pulsar timing arrays (PTA). If $\Lambda\neq 0$ it turns out that waves are anharmonic in cosmological…
With the increase in the number of observed gravitational wave (GW) signals, detecting strongly lensed GWs by galaxies has become a real possibility. Lens galaxies also contain microlenses (e.g., stars and black holes), introducing further…
The four observables associated with gravitational lensing of distant quasars by intervening galaxies: image splittings, relative amplifications, time delays, and optical depths, provide separate measures of the strength of the…
We study second order gravitational effects of local inhomogeneities on the cosmic microwave background radiation in flat universes with matter and a cosmological constant $\Lambda$. We find that the general relativistic correction to the…
LISA might detect gravitational waves from mergers of massive black hole binaries strongly lensed by intervening galaxies (Sereno et al. 2010). The detection of multiple gravitational lensing events would provide a new tool for cosmography.…
A simple estimate is given of gravitational wave memory for the inspiral and merger of a binary black hole system. Here the memory is proportional to the total energy radiated and has a simple angular dependence. This estimate might be…
We review theory and applications of weak gravitational lensing. After summarising Friedmann-Lemaitre cosmological models, we present the formalism of gravitational lensing and light propagation in arbitrary space-times. We discuss how…
Gravitational-wave experiments with interferometers and with resonant masses can search for stochastic backgrounds of gravitational waves of cosmological origin. We review both experimental and theoretical aspects of the search for these…
The gravitational memory effects of Chern-Simons modified gravity are considered in the asymptotically flat spacetime. If the Chern-Simons scalar does not directly couple with the ordinary matter fields, there are also displacement, spin…
There is an extremely simple relationship between the spectrum of the gravitational wave background produced by a cosmological distribution of discrete gravitational wave sources, the total time-integrated energy spectrum of an individual…
Frequency-dependent gravitational lens effects are found for trajectories of electromagnetic rays passing through a distribution of plasma near a massive object. Ray propagation through plasma adds extra terms to the equations of motion…
Gravitational lensing is an invaluable probe of the nature of dark matter, and the structures it forms. Lensed gravitational waves in particular allow for unparalleled sensitivity to small scale structures within the lenses, due to the…
Large-scale surveys allow us to construct cosmological probes such as galaxy clustering, weak gravitational lensing, the luminosity distance, and cosmic microwave background anisotropies. The gauge-invariant descriptions of these…