Israeli scientists publish gravitational-wave discovery that won Physics Nobel Prize
Scientists at Tel Aviv University’s School of Physics and Astronomy, the Weizmann Institute of Science in Rehovot and the Hebrew University of Jerusalem’s Racah Institute of Physics have used Nobel Prize-winning research to expand our understanding of the universe.
They confirmed and analyzed data from recently discovered gravitational waves that were predicted by Albert Einstein a century ago and have been detected following the collision of neutron stars 120 million light-years away. This discovery, which first combines measurements of light and gravitational waves, heralds a new era in the study of the universe.
The first neutron star, the collapsed core of a star 10 to 29 times larger than the Sun, was discovered in 1967 by Antony Hewish and Samuel Okoye. Hewish received the 1974 Nobel Prize in Physics for this discovery. Also in 1974, a pair of neutron stars rotating around each other – forming a binary star system – was discovered by Russell Alan Hulse and Joseph Hooton Taylor, Jr., earning them the 1993 Nobel Prize in Physics.
Then on September 14, 2015, scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Louisiana and Washington and the Virgo detector in Italy finally detected the first gravitational waves – “ripples in space” – produced by the merger of two neutron stars.
On October 3, the 2017 Nobel Prize in Physics was awarded to the creators of the LIGO instruments and their detection of gravitational waves – Americans Rainer Weiss, Barry Barish and Kip Thorne.
It was revealed on Monday that gravitational scientists at Tel Aviv University (TAU) have been racing to use results from the LIGO experiments to increase our understanding of the universe. The news of the neutron star collision was apparently leaked to some media sources in August, but their work has just been officially published in Nature and in Science. Additional TAU studies appear in the Astrophysical Journal.
“This is a milestone in the growing effort by scientists worldwide to unlock the mysteries of the universe and of earth,” said Prof. Ehud Nakar of TAU’s School of Physics and Astronomy, who together with his graduate student Ore Gottlieb led the theoretical analysis for the new studies on the discovery that appear in Science.
The two additional studies in Nature and in the Astrophysical Journal were led by Dr. Yair Arcavi of the University of California at Santa Barbara, who will join TAU’s School of Physics and Astronomy next year, in collaboration with Prof. Dovi Poznanski and Prof. Dan Maoz and their students at the school. “This is only the beginning,” said Maoz. “We expect many surprising discoveries in the coming years.”
The existence of gravitational waves provides valuable information about the evolution of exploding neutron stars, as well as the origin of gold, uranium and other heavy metals on earth.
“It is difficult to exaggerate the importance of this discovery,” exulted Poznanksi. “Until recently, we could observe the universe only through light waves that reached us. This new ability to study gravitational waves is analogous to a sense of touch. It’s as though we now have the ability to explore the universe through both sight and touch.”
“This discovery has allowed astronomers to combine gravitational waves with light and produce a detailed model of the emission for the first time. This introduces a new era in astronomy,” added Gottlieb.
A neutron star forms when a star much bigger and brighter than the sun exhausts its thermonuclear fuel supply and explodes into a violent supernova. The explosion of extremely dense neutron stars, which are made almost entirely of neutrons, was detected by multiple telescopes across the electromagnetic spectrum, from gamma rays and visible light to radio waves.