Fifty Years of Black Hole Evaporation

Event Date:
2025-09-23T16:00:00
2025-09-23T17:00:00
Event Location:
HENN 318
Speaker:
William G. Unruh, UBC and Texas A&M University
URL:
Zoom link
Related Upcoming Events:
Pioneers in Theoretical Physics
Intended Audience:
Everyone
Local Contact:

Gordon Semenoff (gordonws@phas.ubc.ca)

All are welcome to the start of this year's Pioneers in Theoretical Physics colloquium series!

*Refreshments will be provided before the talk at 3:45pm and the talk will start at 4:00pm

Zoom link: https://ubc.zoom.us/j/65528273976?pwd=yl5plR47hOEfdKUxDyFaqH4vAvAcTa.1 

Meeting ID: 655 2827 3976
Passcode: 410191
SIP: 65528273976@vn.zmca.us

Event Information:

Abstract:

In 1974, Stephen Hawking predicted that a black hole, formed by the collapse of matter like a star, should not be black, as seemed to be the prediction since the surface is an outward going null "shell" from which nothing can escape, but rather should emit a thermal bath of radiation with a temperature inversely proportional to the mass of the black hole. But where does this radiation come from? It cannot be from the inside of the black hole, since wouldn't it have to travel faster than light to do so? At almost the same time I predicted that in the vacuum in flat spacetime, an accelerated "detector" (atom, photon counter, Geiger counter,...) should respond as if surrounded by a thermal bath whose temperature was proportional to its acceleration. This turned out to be closely related to Hawking's result. 

I will present a very personal history of the past 50 years as we have tried to understand this quantum phenomenon. What is the origin of Black hole thermodynamics? 50 years later this is still one of the big questions in the overlap between quantum field theory and gravity.
 

Bio:

William Unruh is a Professor of Physics at the University of British Columbia who has made seminal contributions to our understanding of gravity, black holes, cosmology, quantum fields in curved spaces, and the foundations of quantum mechanics, including the discovery of the Unruh effect. His investigations into the effects of quantum mechanics of the earliest stages of the universe have yielded many insights, including the effects of quantum mechanics on computation. Dr. Unruh was the first Director of the Cosmology and Gravity Program at the Canadian Institute for Advanced Research (1985-1996). His many awards include the Rutherford Medal of the Royal Society of Canada (1982), the Herzberg Medal of the Canadian Association of Physicists (1983), the Steacie Prize from the National Research Council (1984), the Canadian Association of Physicists Medal of Achievement (1995), and the Canada Council Killam Prize. He is an elected Fellow of the Royal Society of Canada, a Fellow of the American Physical Society, a Fellow of the Royal Society of London, and a Foreign Honorary Member of the American Academy of Arts and Science. [From the Perimeter Institute website: Bill Unruh | Perimeter Institute] 

Learn More:

 

Add to Calendar 2025-09-23T16:00:00 2025-09-23T17:00:00 Fifty Years of Black Hole Evaporation Event Information: Abstract: In 1974, Stephen Hawking predicted that a black hole, formed by the collapse of matter like a star, should not be black, as seemed to be the prediction since the surface is an outward going null "shell" from which nothing can escape, but rather should emit a thermal bath of radiation with a temperature inversely proportional to the mass of the black hole. But where does this radiation come from? It cannot be from the inside of the black hole, since wouldn't it have to travel faster than light to do so? At almost the same time I predicted that in the vacuum in flat spacetime, an accelerated "detector" (atom, photon counter, Geiger counter,...) should respond as if surrounded by a thermal bath whose temperature was proportional to its acceleration. This turned out to be closely related to Hawking's result.  I will present a very personal history of the past 50 years as we have tried to understand this quantum phenomenon. What is the origin of Black hole thermodynamics? 50 years later this is still one of the big questions in the overlap between quantum field theory and gravity.  Bio: William Unruh is a Professor of Physics at the University of British Columbia who has made seminal contributions to our understanding of gravity, black holes, cosmology, quantum fields in curved spaces, and the foundations of quantum mechanics, including the discovery of the Unruh effect. His investigations into the effects of quantum mechanics of the earliest stages of the universe have yielded many insights, including the effects of quantum mechanics on computation. Dr. Unruh was the first Director of the Cosmology and Gravity Program at the Canadian Institute for Advanced Research (1985-1996). His many awards include the Rutherford Medal of the Royal Society of Canada (1982), the Herzberg Medal of the Canadian Association of Physicists (1983), the Steacie Prize from the National Research Council (1984), the Canadian Association of Physicists Medal of Achievement (1995), and the Canada Council Killam Prize. He is an elected Fellow of the Royal Society of Canada, a Fellow of the American Physical Society, a Fellow of the Royal Society of London, and a Foreign Honorary Member of the American Academy of Arts and Science. [From the Perimeter Institute website: Bill Unruh | Perimeter Institute]  Learn More: Bill's faculty page: unruh | UBC Physics & Astronomy Bill's webpage from the Perimeter Institute: Bill Unruh | Perimeter Institute The "Unruh effect": youtube What is Quantum Field theory: Quantum field theory | Definition & Facts | Britannica and Gravity: Gravity. Find more research papers on Quantum Field Theory & Gravity here by PHAS professor Mark Van Raamsdonk here: Literature Search - INSPIRE What Are Black Holes? - NASA ‘Loudest’ black hole ever detected, 10 years after Nobel-winning discovery | UBC Science    Event Location: HENN 318