Physics Seminar: From the Possibility to the Certainty of a Supermassive Black Hole

Greetings,

The Physics seminar this week will meet on Friday, November 8 at 3:00 pm.  You can join online at this link:  https://wright.webex.com/meet/sarah.tebbens

The speaker this week will be Dr. Andrea Ghez  (pre-recorded).  The talk was originally presented in 2020 when Dr. Ghez was awarded a 1/4 share of the 2020 Nobel Prize in Physics.  

The talk is titled, “From the Possibility to the Certainty of a Supermassive Black Hole."

I hope you can join us,

Dr. Tebbens

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Black holes and the Milky Way’s darkest secret

The 2020 Nobel Prize in Physics was shared by three scientists.

Roger Penrose invented ingenious mathematical methods to explore Albert Einstein’s general theory of relativity. He showed that the theory leads to the formation of black holes, those monsters in time and space that capture everything that enters them. Nothing, not even light, can escape.

Reinhard Genzel and Andrea Ghez each lead a group of astronomers that, since the early 1990s, has focused on a region called Sagittarius A* at the centre of our galaxy. The orbits of the brightest stars closest to the middle of the Milky Way have been mapped with increasing precision. The measurements of these two groups agree, with both finding an extremely heavy, invisible object that pulls on the jumble of stars, causing them to rush around at dizzying speeds. Around four million solar masses are packed together in a region no larger than our solar system.

Using the world’s largest telescopes, Genzel and Ghez developed methods to see through the huge clouds of interstellar gas and dust to the centre of the Milky Way. Stretching the limits of technology, they refined new techniques to compensate for distortions caused by the Earth’s atmosphere, building unique instruments and committing themselves to long-term research. Their pioneering work has given us the most convincing evidence yet of a supermassive black hole at the centre of the Milky Way.

“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”, says David Haviland, chair of the Nobel Committee for Physics.