Tests of General Relativity with GW170817

Abstract

The recent discovery by Advanced LIGO and Advanced Virgo of a gravitational wave signal from a binary neutron star inspiral has enabled tests of general relativity (GR) with this new type of source. This source, for the first time, permits tests of strong-field dynamics of compact binaries in the presence of matter. In this Letter, we place constraints on the dipole radiation and possible deviations from GR in the post-Newtonian coefficients that govern the inspiral regime. Bounds on modified dispersion of gravitational waves are obtained; in combination with information from the observed electromagnetic counterpart we can also constrain effects due to large extra dimensions. Finally, the polarization content of the gravitational wave signal is studied. The results of all tests performed here show good agreement with GR.

Constraining gravity with eccentric gravitational waves: projected upper bounds and model selection

“…The Laser Interferometer Gravitational-Wave Observatory (LIGO), its Italian counter-part Virgo, and other soon to be operational ground based gravitational wave (GW) detectors are positioned to probe the validity of general relativity (GR) and modified theories of gravity in the dynamical and non-linear strong field regime [1,2]. Indeed with the growing number of current detections [3], we have been able to constrain the mass of the graviton, generic parameterized post-Einsteinian (ppE) deviations in the waveform, and the number spacetime dimensions to name a few effects [4][5][6]. As we add new types of detectors and observe different types of sources, our ability to constrain modified gravity will only improve, as the strength of constraints depends heavily on the system observed.…”

Spherically symmetric solutions in torsion bigravity

“…General Relativity (GR), has, so far, been found to be in excellent accord with all gravitational observations and experiments. In particular, its foundational stone, the weak equivalence principle, has been recently confirmed at the 10 −14 level [1], while gravitational-wave observations have confirmed several basic dynamical predictions of GR [2,3]. [See, e.g., chapter 20 in Ref.…”

“…One of these classes of theories (with torsion propagating both massive 2 + and massive 0 − excitations) has recently been studied with the hope that the massive spin-2 field it contains will define a new, more geometric, solution to having a healthy and cosmologically relevant infrared modification of gravity [25,26]. We recall that the physics of an ordinary, massive 3 Fierz-Pauli-type [27][28][29] spin-2 field raises many subtle issues going by the names of: vanDam-Veltman-Zakharov discontinuity [30,31], Vainshtein (conjectured) mechanism [32], and Boulware-Deser ghost [33]. A breakthrough in the problem of defining a class of consistent, ghost-free nonlinear theories of a massive spin-2 field was achieved in Ref.…”

Science case for the Einstein telescope

“…Concerning fundamental physics, cosmology and General Relativity (GR), the observation of the GWs and the gamma-ray burst from the NS-NS binary GW170817 proved that the speed of GWs is the same as the speed of light to about a part in 10 15 [5]; the GW signal, together with the electromagnetic determination of the redshift of the source, provided the first measurement of the Hubble constant with GWs [17]; the tail of the waveform of the first observed event, GW150914, showed oscillations consistent with the prediction from General Relativity for the quasi-normal modes of the final BH [18]; several possible deviations from GR (graviton mass, post-Newtonian coefficients, modified dispersion relations, etc.) could be tested and bounded [18][19][20]. Extraordinary as they are, these results can however be considered only as a first step toward our exploration of the Universe with GWs.…”