{"id":22380,"date":"2020-10-09T18:39:15","date_gmt":"2020-10-09T18:39:15","guid":{"rendered":"https:\/\/www.lifeandnews.com\/articles\/?p=22380"},"modified":"2020-10-10T02:38:28","modified_gmt":"2020-10-10T02:38:28","slug":"2020-nobel-prize-in-physics-awarded-for-work-on-black-holes-an-astrophysicist-explains-the-trailblazing-discoveries","status":"publish","type":"post","link":"https:\/\/www.lifeandnews.com\/articles\/2020-nobel-prize-in-physics-awarded-for-work-on-black-holes-an-astrophysicist-explains-the-trailblazing-discoveries\/","title":{"rendered":"2020 Nobel Prize in physics awarded for work on black holes \u2013 an astrophysicist explains the trailblazing discoveries"},"content":{"rendered":"

Gaurav Khanna<\/a>, University of Massachusetts Dartmouth<\/a><\/em><\/p>\n

Black holes are perhaps the most mysterious objects in nature. They warp space and time in extreme ways and contain a mathematical impossibility, a singularity \u2013 an infinitely hot and dense object within. But if black holes exist and are truly black, how exactly would we ever be able to make an observation?<\/p>\n

\"\"<\/a>
Andrea Ghez, the fourth woman to win the Nobel Prize in physics.<\/span>
\nFrederick M. Brown\/Getty Images<\/a><\/span><\/figcaption><\/figure>\n

This morning the Nobel Committee announced that the 2020 Nobel Prize in physics<\/a> will be awarded to three scientists \u2013 Sir Roger Penrose,<\/a> Reinhard Genzel<\/a> and Andrea Ghez<\/a> \u2013 who helped discover the answers to such profound questions. Andrea Ghez is only the fourth woman to win the Nobel Prize in physics.<\/p>\n

Robert Penrose is a theoretical physicist who works on black holes<\/a>, and his work has influenced not just me but my entire generation through his series of popular books<\/a> that are loaded with his exquisite hand-drawn illustrations of deep physical concepts.<\/p>\n

\"\"<\/a>
Roger Penrose was famous for his detailed illustrations. This is one of his diagrams of an empty universe.<\/span>
\nRoger Penrose via Wikimedia<\/a>, CC BY-ND<\/a><\/span><\/figcaption><\/figure>\n

As a graduate student in the 1990s at Penn State, where Penrose holds a visiting position, I had many opportunities to interact with him. For many years I was intimidated by this giant in my field, only stealing glimpses of him working in his office, sketching strange-looking scientific drawings on his blackboard. Later, when I finally got the courage to speak with him, I quickly realized that he is among the most approachable people around.<\/p>\n

Dying stars form black holes<\/h2>\n

Sir Roger Penrose<\/a> won half the prize for his seminal work in 1965 which proved, using a series of mathematical arguments, that under very general conditions, collapsing matter would trigger the formation of a black hole.<\/p>\n

This rigorous result opened up the possibility that the astrophysical process of gravitational collapse, which occurs when a star runs out of its nuclear fuel, would lead to the formation of black holes in nature. He was also able to show that at the heart of a black hole must lie a physical singularity \u2013 an object with infinite density, where the laws of physics simply break down. At the singularity, our very conceptions of space, time and matter fall apart and resolving this issue is perhaps the biggest open problem in theoretical physics today.<\/p>\n

Penrose invented new mathematical concepts and techniques<\/a> while developing this proof. Those equations that Penrose derived in 1965 have been used by physicists studying black holes ever since. In fact, just a few years later, Stephen Hawking, alongside Penrose, used the same mathematical tools to prove that the Big Bang cosmological model \u2013 our current best model for how the entire universe came into existence \u2013 had a singularity at the very initial moment. These are results from the celebrated Penrose-Hawking Singularity Theorem<\/a>.<\/p>\n

The fact that mathematics demonstrated that astrophysical black holes may exactly exist in nature is exactly what has energized the quest to search for them using astronomical techniques. Indeed, since Penrose\u2019s work in the 1960s, numerous black holes have been identified.<\/p>\n

[Expertise in your inbox. Sign up for The Conversation\u2019s newsletter and get expert takes on today\u2019s news, every day.<\/a><\/em>]<\/p>\n

Black holes play yo-yo with stars<\/h2>\n

The remaining half of the prize was shared between astronomers Reinhard Genzel and Andrea Ghez, who each lead a team that discovered the presence of a supermassive black hole, 4 million times more massive than the Sun, at the center of our Milky Way galaxy<\/a>.<\/p>\n

Genzel is an astrophysicist at the Max Planck Institute for Extraterrestrial Physics, Germany and the University of California, Berkeley. Ghez is an astronomer at the University of California, Los Angeles.<\/p>\n

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The location of the black hole in the Milky Way galaxy relative to our solar system.<\/span>
\nJohan Jarnestad\/The Royal Swedish Academy of Sciences<\/a>, CC BY-NC<\/a><\/span><\/figcaption><\/figure>\n

Genzhel and Ghez used the world\u2019s largest telescopes (Keck Observatory and the Very Large Telescope) and studied the movement of stars in a region called Sagittarius A* at the center of our galaxy. They both independently discovered that an extremely massive \u2013 4 million times more massive than our Sun \u2013 invisible object is pulling on these stars, making them move in very unusual ways. This is considered the most convincing evidence of a black hole at the center of our galaxy.<\/p>\n