Hawking Radiation (Lecture

Part 5 Black Holes (Book Ch 7, and video lectures #18 to #20)
Course textbook: A College Course on Relativity and Cosmology by Ta-Pei Cheng
https://global.oup.com/academic/produ...

Description: The gravity of a black hole is so strong, and the spacetime so warped, that the roles of space and time are interchanged across its event horizon. For black holes to be relevant for realistic astrophysical situations one must first demonstrate that ordinary stars over a certain mass limit eventually undergo gravitational collapse into black holes. The gravitational binding energy of matter around a black hole is extraordinarily large, giving rise to many energetic events observed in the universe. While no signal can be transmitted from the interior of a black hole in classical physics; quantum fluctuation around a BH can bring about Hawking radiation -- the thermal emission of particles and light from a black hole.

Learning objective: Understanding the spacetime structure of black holes, showing that the lightcones tip over when crossing the event horizon so that no signal can leave the BH. Such classical consideration leads one to conclude that nothing can ever come out of a black hole, but in the context of quantum field theory in curved spacetime, there will be thermal emission known as Hawking radiation.