Gravitational-Wave Constraints on an Effective Field-Theory Extension of General Relativity

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 constraints on an effective field-theory based extension of General Relativity in which only higher-order curvature terms are added to the Einstein-Hilbert action. We construct gravitational-wave templates describing the quasi-circular, adiabatic inspiral phase of binary black holes in this extended theory of gravity. Then, after explaining how to properly take into account the region of validity of the effective field theory when performing tests of General Relativity, we perform Bayesian model selection using the two lowest-mass binary black-hole events reported to date by LIGO and Virgo -- GW151226 and GW170608 -- and constrain this theory with respect to General Relativity. We find that these data disfavors the appearance of new physics on distance scales around $\sim 150$ km. Finally, we describe a general strategy for improving constraints as more observations will become available with future detectors on the ground and in space.