Related papers: Overcoming the SQL in gravitational wave detectors…
According to General Relativity (GR), gravitational waves (GWs) should travel at the speed of light $c$. However, some theories beyond GR predict deviations of the velocity of GWs $c_{\rm gw}$ from $c$, and some of those expect vacuum…
Quantum mechanics dictates that a continuous measurement of the position of an object imposes a random back action perturbation on its momentum. This randomness translates with time into position uncertainty, thus leading to the well known…
Einstein's General Theory of Relativity predicted the existence of gravitational waves (GWs), which offer a way to explore cosmic events like binary mergers and could help resolve the Hubble Tension. The Hubble Tension refers to the…
We have set a new upper limit on the stochastic gravitational wave background (SGWB) using two prototype Torsion-bar Antennas (TOBAs). TOBA is a low-frequency gravitational-wave detector with bar-shaped test masses rotated by the tidal…
We derive a general procedure for calculating the gravitational wave background (GWB) from cosmic string loops whose typical shape evolves over time, as in gravitational backreaction. Using the results of a large-scale study of numerical…
Many astronomical surveys are limited by the brightness of the sources, and gravitational-wave searches are no exception. The detectability of gravitational waves from merging binaries is affected by the mass and spin of the constituent…
A stochastic gravitational wave background (SGWB) would gravitationally lens the cosmic microwave background (CMB) photons. We find that the lensing due to gravitational waves(GW) is more efficient as compared to lensing due to scalar…
Gravitational waves provide a novel and independent measurement of cosmological parameters, offering a promising avenue to address the Hubble tension alongside traditional electromagnetic observations. In the absence of electromagnetic…
The detection of gravitational waves opened up a new window to look into the Universe by probing phenomena invisible through electromagnetic observations. As gravitational waves interact very weakly with matter, their detection is…
Gravitational waves modulate the apparent frequencies of other periodic signals. Low-frequency gravitational waves could therefore be detected by observing frequency modulations in signals from higher-frequency sources, e.g., those from…
Gravitational wave detectors are typically described as responding to gravitational wave metric perturbations, which are gauge-dependent and --- correspondingly --- unphysical quantities. This is particularly true for ground-based…
Gravitational-wave observations of coalescing binary systems allow for novel tests of the strong-field regime of gravity. Using data from the Gravitational Wave Open Science Center (GWOSC) of the LIGO and Virgo detectors, we place the first…
The causal tail of stochastic gravitational waves can be used to probe the energy density in free streaming relativistic species as well as measure $g_\star(T)$ and beta functions $\beta(T)$ as a function of temperature. In the event of the…
Gravitational waves from the coalescence of compact binaries, together with an associated electromagnetic counterpart, are ideal probes of cosmological models. As demonstrated with GW170817, such multimessenger observations allow one to use…
Dimensional flow, the scale dependence of the dimensionality of spacetime, is a feature shared by many theories of quantum gravity (QG). We present the first study of the consequences of QG dimensional flow for the luminosity distance…
The subtle influence of gravitational waves on the apparent positioning of celestial bodies offers novel observational windows. We calculate the expected astrometric signal induced by an isotropic Stochastic Gravitational Wave Background…
We discuss the ability of the SKA to observe QSO proper motions induced by long-wavelength gravitational radiation. We find that the SKA, configured for VLBI with multiple beams at high frequency (8 GHz), is sensitive to a dimensionless…
Space-based gravitational-wave detectors, such as LISA or a similar ESA-led mission, will offer unique opportunities to test general relativity. We study the bounds that space-based detectors could place on the graviton Compton wavelength…
Quantum electro dynamics (QED) comprises virtual particle production and thus gives rise to a refractive index of the vacuum larger than unity in the presence of a magnetic field. This predicted effect has not been measured to date, even…
Gravitational-wave (GW) observations of binary black-hole (BBH) coalescences are expected to address outstanding questions in astrophysics, cosmology, and fundamental physics. Realizing the full discovery potential of upcoming…