One half of the prize went to Roger Penrose, a physicist, mathematician and cosmologist at the University of Oxford who worked with a fellow physicist, the late Stephen Hawking, to merge Einstein's theory of relativity with quantum theory to suggest that space and time would begin with the Big Bang and end in black holes. The other half was awarded to Ghez and Reinhard Genzel, who is director at the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, and a professor at UC Berkeley.
Penrose was awarded "for the discovery that black hole formation is a robust prediction of the general theory of relativity." Genzel and Ghez were honored by the Royal Swedish Academy of Sciences "for the discovery of a supermassive compact object at the center of our galaxy."
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"I think today I feel more passionate about the teaching side of my job than I have ever," Ghez said after the prize was announced in Stockholm, Sweden.
Ghez, who is director of the UCLA Galactic Center Group, said that "the research the Nobel committee is honoring today is the product of a wonderful collaboration among the scientists in the UCLA Galactic Center Orbits Initiative and the University of California's wise investment in the W.M. Keck Observatory'' in Hawaii.
In July 2019, the journal Science published a study by Ghez and her research group regarded as the most comprehensive test of Albert Einstein's iconic general theory of relativity near the huge black hole at the center of our galaxy. Although she concluded that "Einstein's right, at least for now,'' the research group is continuing to test Einstein's theory, which she says cannot fully explain gravity inside a black hole.
Ghez studies more than 3,000 stars that orbit the supermassive black hole. Black holes have such high density that nothing can escape their gravitational pull, not even light. The center of the vast majority of galaxies appears to have a supermassive black hole, she said.
Ghez suggested that winning the Nobel Prize was but a milestone on a scholastic odyssey.
"We have cutting-edge tools and a world-class research team, and that combination makes discovery tremendous fun. Our understanding of how the universe works is still so incomplete. The Nobel Prize is fabulous, but we still have a lot to learn.''
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As the fourth woman to receive the physics prize, Ghez follows Marie Curie in 1903, Maria Goeppert Mayer in 1963 and, 55 years later, Donna Strickland in 2018. The 55-year-old New York-born Ghez attended both the California Institute of Technology and the Massachusetts Institute of Technology. She authored the book, You Can Be a Woman Astronomer.
UCLA Chancellor Gene Block lauded Ghez for her accomplishments.
"The UCLA community is exceedingly proud of Professor Ghez's achievements, including this extraordinary honor,'' Block said. "We are inspired by her research uncovering the secrets of our universe and its potential to help us better understand the cosmos.''
The Nobel Prize in Chemistry will be announced on Wednesday, followed by the Nobel Prize in Literature on Thursday, the Nobel Peace Prize on Friday and the Prize in Economic Sciences next Monday. This year's Nobel Prize in Medicine was awarded to three researchers on Monday for the discovery of hepatitis C virus, leading to the development of tests and treatments.
City News Service contributed to this report.