Tests of General Relativity with the Binary Black Hole Signals from the LIGO-Virgo Catalog GWTC-1

The detection of gravitational wavesby Advanced LIGOand Advanced Virgo provides an opportunity to test general relativityin a regime that is inaccessible to traditional astronomical observations and laboratory tests. We present four tests of the consistency of the data with binary black holegravitational waveforms predicted by general relativity. One test subtracts the best-fit waveform from the data and checks the consistency of the residual with detector noise. The second test checks the consistency of the low- and high-frequency parts of the observed signals. The third test checks that phenomenological deviations introduced in the waveform model (including in the post-Newtonian coefficients) are consistent with zero. The fourth test constrains modifications to the propagation of gravitational wavesdue to a modified dispersion relation, including that from a massive graviton. We present results both for individual events and also results obtained by combining together particularly strong events from the first and second observing runs of Advanced LIGOand Advanced Virgo, as collected in the catalog GWTC-1. We do not find any inconsistency of the data with the predictions of general relativityand improve our previously presented combined constraints by factors of 1.1 to 2.4. In particular, we bound the mass of the gravitonto be $m_g \leq 5.0 \times 10^{-23} \text{eV}/c^2$ ($90\%$ credible level), an improvement of a factor of 1.5 over our previously presented results. Additionally, we check that the four gravitational-waveevents published for the first time in GWTC-1 do not lead to stronger constraints on alternative polarizations than those published previously.