Gravitational Radiation and the Validity of General Relativity

While the detection of gravitational radiation may usher in a new era of “gravitational wave” astronomy (see the accompanying article by Barry Barish and Rainer Weiss, on page 44), it should also yield new and interesting tests of Einstein's general theory of relativity, especially in the radiative and strong‐field regimes. Consequently, we are in an unusual situation. After all, we rarely think of electromagnetic astronomy as providing tests of Maxwell's theory. Neutrino astronomy may be a closer cousin: We can observe neutrinos to learn about the solar interior or about supernovae, while also checking such fundamental phenomena as neutrino oscillations. To some extent, the usefulness of astronomical observations in testing fundamental theory depends upon how well tested the theory is already. At the same time, since general relativity is the basis for virtually all discussion of gravitational‐wave detectors and sources, the extent of its “upfront” validity is of some concern to us.