An unusual way

On Oct 6, Roger Penrose from the UK, Reinhard Genzel from Germany, and Andrea Ghez from the US won the Nobel Prize in Physics for their discoveries on the black hole.

Penrose, Emeritus Rouse Ball Professor of Mathematics at the University of Oxford and a contemporary of the late UK theoretical physicist Stephen Hawking, was awarded 50 percent of the prize money of 10 million Swedish krona ($1.14 million) for his work on using mathematics to prove that black holes are a direct consequence of Albert Einstein's Theory of General Relativity.

The remainder of the prize money went to Genzel and Ghez for discovering that an invisible and extremely heavy object governs the orbits of stars at the center of our galaxy.

Penrose, 89, told reporters, "It was an extreme honor and great pleasure to hear the news this morning in a slightly unusual way－I had to get out of my shower to hear it."

Ghez, a professor in the Department of Physics and Astronomy at the University of California, Los Angeles, is only the fourth woman awarded the Physics prize, after Marie Curie in 1903, Maria Goeppert-Mayer in 1963 and Donna Strickland in 2018.

She said she hoped her win would inspire other women to enter the fields of astronomy and astrophysics.

Asked about the moment of scientific discovery, Ghez said her first thought was doubt.

"You have to prove to yourself that what you are really seeing is what you think you are seeing. So, both doubt and excitement," the 55-year-old said in a phone call with the committee after receiving the award. "It's that feeling of being at the frontier of research when you have to always question what you are seeing."

Genzel, director of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, and a professor emeritus of physics and astronomy at the University of California, Berkeley, told Reuters Television he was on a Zoom call with colleagues when the phone rang.

"Just like in the movies, a voice said: 'This is Stockholm'," the 68-year-old said, adding that he "cried a little bit".

In 1915, Einstein predicted in his Theory of General Relativity that space and time could be warped by the force of gravity. However, he did not actually believe in black holes, and finding a way to prove their existence baffled scientists for another 50 years.

In a seminal paper in 1965, Penrose proved that black holes can really form－describing them in detail and stating that, at their center, there is a singularity where time and space cease to exist.

Asked by Reuters about the biggest riddle concerning black holes, Penrose said, "The greatest puzzle is the singularities, because we don't know what to do with them－you see, the black holes shield us from the singularities."

Speaking from Oxford, he told reporters, "As the matter collapses into the middle, the densities get larger and larger and they just exceed everything you can think of."

For more than a decade, starting in the early 1990s, Genzel and Ghez individually led research into Sagittarius A*, a region at the center of the Milky Way galaxy. Through observing the unusual orbits of stars, they were able to infer the existence of a gigantic object in the center of the galaxy. Current scientific consensus holds that this object is a supermassive black hole.

David Haviland, chair of the Nobel Committee for Physics, said: "The discoveries of this year's laureates have broken new ground in the study of compact and supermassive objects, but these exotic objects still pose many questions that beg for answers and motivate future research. Not only questions about their inner structure, but also questions about how to test our theory of gravity under the extreme conditions in the immediate vicinity of a black hole."