Model-independent test of gravity with a network of ground-based gravitational-wave detectors

Abstract

The observation of gravitational waves with a global network of interferometric detectors such as advanced LIGO, advanced Virgo, and KAGRA will make it possible to probe into the nature of space-time structure. Besides Einstein's general theory of relativity, there are several theories of gravitation that passed experimental tests so far. The gravitational-wave observation provides a new experimental test of alternative theories of gravity because a gravitational wave may have at most six independent modes of polarization, of which properties and number of modes are dependent on theories of gravity. This paper develops a method to reconstruct an arbitrary number of modes of polarization in time-series data of an advanced detector network. Since the method does not rely on any specific model, it gives model-independent test of alternative theories of gravity.

Testing General Relativity with Low-Frequency, Space-Based Gravitational-Wave Detectors

“…The use of GW polarization modes to test GR was first proposed in 1973 [160,159]. The sensitivity of resonant and interferometric detectors, as well as Doppler-tracking and pulsar-timing measurements, to the extra modes was considered in several studies [343,227,412,461,292,300,324,280,331,15,118,89,225]. In the most general setting, the problem of disentangling the modes has eight unknowns -the time series for the six polarizations, plus two direction angles that affect the projection of the modes on the detector -but only six observables, corresponding to the R 0i0j components.…”

Frequency response of space-based interferometric gravitational-wave detectors

“…The sensitivity with various power spectra of noises to different polarizations in different frequencies for LISA was studied in [33]. There are also discussions on the response functions of arbitrary polarizations for other detectors satisfying the low frequency limit [34][35][36]. In [37], the author analyzed the angular and frequency behavior and the sensitivity patterns of the responses for arbitrary polarizations with different detector designs.…”

Gravitational waves in theories with a non-minimal curvature-matter coupling

“…[74]: the antenna angular pattern functions of the detector of gravitational waves measures the linear combination of the polarisation states. Thus, the response from combined Gravitational Wave detectors, such as Advanced-LIGO, Advanced-Virgo or Einstein GW Telescope, could be used to distinguish between models of gravity.…”