The path that led from 1915, when Einstein presented his theory, to the detection by the Laser Interferometer Gravitational-Wave Observatory (LIGO) was filled with twists and turns, some dead ends and countless scientific discoveries, said Joseph Taylor, professor emeritus at Princeton University. Among those critical discoveries was one he made in 1974 that earned him the 1993 Nobel Prize in Physics.

On Wednesday, April 24, Taylor will trace that 100-year journey from theory to detection for an audience at the University of Delaware.

His talk, “From Einstein’s Theory to Gravity’s Chirp,” will be given at 7:30 p.m. in Clayton Hall on UD’s Newark campus. Designed for a general-interest audience, the Harcourt Vernon Lecture is sponsored by the Mount Cuba Astronomical Observatory in Greenville, Delaware, in partnership with the University’s Delaware Asteroseismic Research Center and the Mount Cuba Foundation.

The lecture is free and open to the public, but space is limited; please register at this website.

Much of Taylor’s lecture will concern his Nobel Prize-winning discovery, with research student and co-laureate Russell Hulse, of a new type of orbiting pulsar. Pulsars, which are rotating neutron stars that emit pulses of radiation at regular intervals, are observed as beams of light that sweep over the Earth.

Using the radio telescope at Arecibo, Puerto Rico, Taylor and Hulse searched for pulsars and in 1974 discovered the first binary pair of pulsars orbiting each other. Studying the pair over the next several years, scientists found indirect proof of the existence of gravitational waves as predicted by Einstein.

When LIGO detected those waves in 2015, it was the final proof that binary black holes exist and can merge, physicists said. Gravitational waves provide scientists with a new way of observing and learning more about events in space.