Taylor, Joseph Hooton, Jr. (1941-…), an American physicist, discovered the first binary pulsar, a collapsed star emitting huge amounts of energy, orbiting another similar object. His subsequent studies led to a verification of German-born physicist Albert Einstein’s theory of general relativity for a system outside our solar system. For this work, Taylor shared the 1993 Nobel Prize for physics with fellow American Russell Hulse (see Hulse, Russell Alan ).
A pulsar is a rapidly spinning neutron star. An extremely powerful magnetic field surrounds the neutron star and rotates with it. This rapidly rotating magnetic field produces a strong electric field that rips electrons and protons from the star’s surface. As these particles flow from the star, they emit energy in the form of a narrow beam of radio waves. Using a giant radio telescope, an astronomer can detect a pulse of radio waves each time the pulsar rotates and the beam sweeps past the earth.
In 1974, Taylor and Hulse, using the huge Arecibo Observatory radio telescope in Puerto Rico, found a pulsar where the rate of pulsation regularly decreased and increased about a constant average value. They concluded that the pulsar was revolving around an unobserved companion object, the two forming a binary system. The scientists deduced that the pulsar had a companion at a distance corresponding to several times the distance from the earth to the moon. Until the discovery of the binary pulsar, known as PSR 1913+16, scientists had believed that the supernova explosion in which any pulsar is formed would inevitably destroy all companion objects. Taylor went on to find more binary pulsars.
Taylor and Hulse studied the pulse sequence and worked out the orbit of the system. By recording the pulses over several years, Taylor and Hulse noted a gradual slowdown of the pulsation rate. The pulsars were losing energy and spiraling closer to each other. Their studies confirmed that the massive bodies in orbit around each other give off energy in the form of gravitational waves. Albert Einstein had predicted the existence of gravitational waves in 1915 as part of his general theory of relativity (see Relativity ). In 2016, researchers announced that they had directly detected the existence of gravitational waves.
Taylor was born in Philadelphia. He graduated from Haverford College in Pennsylvania in 1963, having built a working radio telescope as an honors project. He went on to Harvard University to do research in radio astronomy. Having gained his Ph.D. from Harvard in 1968, Taylor became a member of the faculty of the University of Massachusetts the following year. In the early 1970’s, he supervised the work of Russell Hulse, who was studying radio astronomy as part his post-graduate work. Taylor became a professor of physics at Princeton University in 1980 and, in 1986, was named the James S. McDonnell Distinguished University Professor of Physics at Princeton.
