LCGT shall be planned to be the first-generation detector with an advanced technique for employing a cryogenic mirror in order to firstly detect a gravitational wave, and after detection, the detector will serve as an astronomical tool to observe the Universe through gravitational wave radiation. In collaborative observation with the LIGO, GEO and Virgo projects, LCGT desires to contribute to t...

We report the results of testing gravitational-wave birefringence using largest population events currently available. Gravitational-wave birefringence, which can arise from effective field theory extension general relativity, occurs when parity symmetry is broken, causing left- and right-handed polarizations to propagate following different equations motion. perform Bayesian inference on 94 re...

We present an overview of quantum noise in gravitational wave interferometers. Current gravitational wave detectors are modified variants of a Michelson interferometer and the quantum noise limits are strongly influenced by the optical configuration of the interferometer. We describe recent developments in the treatment of quantum noise in the complex interferometers of present-day and future g...

This cataclysmic event, producing the gravitational-wave signal GW150914, took place in a distant galaxy more than one billion light years from the Earth. It was observed on September 14, 2015 by the two detectors of the Laser Interferometer Gravitational-wave Observatory (LIGO), arguably the most sensitive scientific instruments ever constructed. LIGO estimated that the peak gravitational-wave...

In this review we examine the dynamics and gravitational wave detectability of rotating strained neutron stars. The discussion is divided into two halves: triaxial stars, and precessing stars. We summarise recent work on how crustal strains and magnetic fields can sustain triaxiality, and suggest that Magnus forces connected with pinned superfluid vortices might contribute to deformation also. ...

A spherical gravitational wave antenna is distinct from other types of gravitational wave antennas in that only a single detector is necessary to determine the direction and polarization of a gravitational wave. Zhou and Michelson showed that the inverse problem can be solved using the maximum likelihood method if the detector outputs are independent and have normally distributed noise with the...

We report the results of the first joint search for gravitational waves by the TAMA and LIGO collaborations. We looked for millisecond-scale unmodelled gravitational-wave bursts in 473hr of coincident data collected during early 2003. No candidate signals were found. We set an upper limit of 0.12 events per day on the rate of gravitational-wave transients, at 90% confidence level. Using simulat...

We present results of numerical simulations of sequences of binary-single scattering events of black holes in dense stellar environments. The simulations cover a wide range of mass ratios from equal mass objects to 1000:10:10 M⊙ and compare purely Newtonian simulations to simulations in which Newtonian encounters are interspersed with gravitational wave emission from the binary. In both cases, ...

We consider the stochastic background of gravitational waves produced by a network of cosmic strings and assess their accessibility to current and planned gravitational wave detectors, as well as to big bang nucleosynthesis (BBN), cosmic microwave background (CMB), and pulsar timing constraints. We find that current data from interferometric gravitational wave detectors, such as Laser Interfero...

The direct detection of gravitational radiation (GR) from astrophysical sources is one of the most important outstanding problems in experimental gravitation today. The construction of large laser interferometric gravitational wave detectors like the LIGO, VIRGO , LISA, TAMA 300, GITO 6000 and AIGO is opening a new window for the study of a vast and rich variety of nonlinear curvature phenomena...