A highlight from Prof. Mitch Begelman, Professor of Astrophysical Sciences at the University of Colorado, Boulder
Mike. Yesterday's prefaced each benn. Who is professor professor physical and financial sciences at the university of colorado boulder and defend off the j. l. a. Joined loosens institute of the utah colorado and the national security of standards and technology. He studies aspects of black holes phone girl at interactive as roundings volunteered respect. Then commit blow. Thanks doing this so I want to start with one of your people On black holes from two thousand six entitled formation of supermassive black holes by direct collapse in pre gallic in which you say we describe mechanism by supermassive black holes. Scanned formed directly in the nuclei of foto galaxies without the need for seed. Black hole. Steph tober from star formation up before we get into this mitch black codes Discontinuing space-time alvin mascots concentrated in short spaces Essentially have a discontinuity that that can't quite understand Bugden are different masses of these black holes and some of them are what he calls supermassive black holes that tend to be at the center of galaxies. Right yes yeah so one night. Believe at the center of the milky way galaxy out own galaxy and I i guess. A lot of tilles around healthy are formed so this is one of the hypothesis of yes yup Black holes are places where you have so much. Mass concentrated in such a small region that the gravity of that massive so strong that Dumping can escape it once. It gets trapped in fact They're even weirder than you think. They're not really they're not really necessarily made out of matter they are there places where einstein tells us that gravity is is really the result of space time curvature and their places where where the curvature of space time so kicked up that in fact it's kind of feeds on itself and kind of space gets gets Gets closed in on itself. So in theory factor you could produce a black hole without any mass but in practice i mean just by curving space time but in order to get space-time kicked up enough in practice in the universe we We know that this happens. When large amounts of mass a collapsed small volume now The nearest black holes to us. And by near i mean probably within a few hundred light years so nearby. My standards not necessarily by that of many of the listeners. Those results from the collapse of massive stars. That run out of nuclear fuel in just can't hold themselves up against gravity but we also know that there is a second class of black holes that seems to in which there seems to be one at the center of every day galaxy and There's still a lot of controversy about hope how those could have formed. These black holes are responsible for some dramatic phenomenon such as quasars which are very luminous objects usually founded not far Quite distant places. Yes be back Be think about even horizon and so Like what you're saying is that even christ and a sort of a boundary Once you cross that not even like an escape but it doesn't really mean that sites of the black hole right. It just concept really. Well it's the point of no return.