Neil deGrasse Tyson: Black holes remember what they ate — even after they die
On a recent episode of StarTalk Radio, astrophysicist Neil deGrasse Tyson explained what happened to the energy and matter “eaten” by a black hole when it dies.
Reading a question from a listener, co-host Chuck Nice asked, “is it my understanding that a black hole will just vanish and disappear at the end of its life? If that’s so, and ‘E = mc^2’ what happens to the energy and all the particles in a vanishing black hole?”
“All black holes evaporate,” Tyson answered. “Every understanding of quantum physics and relativity as advanced to us by the brain-work of Stephen Hawking — and in fact, it’s called ‘Hawking radiation’ — its evaporation [creates] an energy field so intense that matter spontaneous spawns in [it].”
“In so doing, the black hole loses mass,” he continued. “It’s losing mass because it’s sending matter and energy out beyond its event horizon.”
“So there’s no loss of mass or energy. ‘E = mc^2’ is still intact. What’s even more amazing is that every atom that went in — if I dropped you into a black hole — there’s an accounting of that.”
“There’s a mysterious quantum accounting of you that went in,” Tyson concluded. “So if you look at the particles that evaporate out from the energy field? That tally will come out equaling the tally of atoms that went in in the first place.”
“The black hole remembers what it ate.”