Reflections on an Astrophysical Clock-Comparison Experiment by Joe Taylor, Nobel Laureate

This presentation was made by Joe Taylor, Nobel Laureate, Princeton University, at IEEE IFCS 2016 in New Orleans. Abstract: Pulsars are rapidly spinning, strongly magnetized neutron stars, the collapsed remnants of supernova explosions. They are sometimes described as nature's most precise clocks. The 1974 discovery of an orbiting pulsar provided a unique opportunity to explore the fundamental nature of gravity beyond the weak-field, slow-motion regime that exists everywhere in the solar system. The resulting clock-comparison experiment firmly established the existence of gravitational waves as predicted by Einstein's general theory of relativity, and lent strong support to the case for ambitious efforts to detect such waves directly. Biography: Using the Arecibo Observatory in Puerto Rico in 1974, Joe Taylor and his student Russel Hulse made the first discovery of a pulsar in a binary system. The orbit of this binary system slowly shrinks as it loses energy from emission of gravitational radiation. Over a thirty-year period Taylor and his colleagues made measurements of the rate of shrinkage of the orbit that match the prediction of General Relativity to much better than 1% accuracy. Together Taylor and Hulse received the 1993 ​Nobel Prize for Physics "for the discovery of a new type of pulsar, a discovery that has opened up new possibilities for the study of gravitation". In addition to the Nobel Prize, Professor Taylor has been recognized with many other awards, including the first Heineman Prize of the American Astronomical Society, the Henry Draper Medal of the National Academy of Sciences, the Tomalla Foundation Prize, the Magellanic Premium, the Carty Award for the Advancement of Science, the Einstein Prize, the Wolf Prize in Physics, and the Schwartzchild Medal. He was also among the first group of MacArthur Fellows. Professor Taylor is the James S. McDonnell Distinguished University Professor in Physics, Emeritus, at Princeton. Joe Taylor is also known by his amateur radio call sign K1JT.