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2020 Nobel Prize for physics goes to pioneering black hole scientists

There’s a black hole at the center of this year’s Nobel Prize for physics. Announced Tuesday, Oxford University mathematician Roger Penrose, Max Planck Institute for Extraterrestrial Physics astronomer Reinhard Genzel, and University of California, Los Angeles astronomer Andrea Ghez will share the 114th Nobel Prize for their pioneering work on the formation of black holes, and the discovery of a giant one at the heart of the Milky Way.

Black holes are regions of spacetime in which the gravity is so strong that not even light can escape from it. The boundary from which no escape is possible from a black hole is called an event horizon. The concept of objects with such significant gravitational fields was suggested as far back as the 18th century, although it took until the 20th century until the idea was considered in more detail. Albert Einstein’s theory of general relativity, for instance, showed that gravity is capable of changing the movement of light. In the 1960s, Penrose showed that black holes could appear generically, rather than as mathematical anomalies. Before this, experts — including Einstein — suggested that black holes don’t exist in physical reality.

Genzel and Ghez, meanwhile, were honored for their work using the world’s largest telescopes to discover a supermassive object in the galaxy, called Sagittarius A*, which could only possibly be a black hole. Imaging a black hole is extremely challenging because, with no light able to get out of them, they are rendered invisible to the naked eye. They can only be observed by using space telescopes with special tools that are able to see how stars in close proximity to a black hole act differently to other stars. When a black hole is near to a star, it creates a high-energy light that can be identified under certain conditions.

“There is a major problem in physics in that we have a wonderful theory about gravity, courtesy of Albert Einstein, and then a beautiful model of everything else in nature that is not related to gravity,” Ralph Scheicher, a researcher in the Department of Physics and Astronomy at Sweden’s Uppsala University, told Digital Trends, explaining why black holes are such a source of fascination. “Both work fantastically well in that they make predictions that match experiments, but they cannot both be right. They don’t fit with each other to form one unified Theory Of Everything. And so scientists look for modifications of either theory. Because black holes are such extreme objects with unimaginably strong gravitational fields, they are a perfect testing ground to observe and test predictions from [the] General Theory of Relativity.”

Genzel and Ghez will share half of the Nobel Prize, while Penrose receives the other half. Ghez is only the fourth woman in history to receive a Nobel Prize for physics since the prize was founded in 1901. Out of more than 200 laureates, only Marie Curie, Maria Goeppert-Mayer, and Donna Strickland are other female laureates to win the physics prize.

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Luke Dormehl
I'm a UK-based tech writer covering Cool Tech at Digital Trends. I've also written for Fast Company, Wired, the Guardian…
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