The black-hole information paradox, complementarity, and firewalls by Leonard Susskind

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1. The audio ... Omg! 😲😲😲😲
2. So I spent the morning looking at what I could find when I typed the words, "Quantum Reality" in the YT search engine. People can be so dumb, it hurts.
3. Alright, I know Lennie doesn't like clip-on mics but someone should impress upon him the value (to future generations) of these lectures. At the very least it would behoove the technicians to put a few good mics at the front of the room. Shameful waste of a permanent record!
4. just an idea: but doesent the paradox only exist due to the limit of knowledge.. if you could see the universe as a hole.. every interaction.. would the information " lost" still be there as a change. this change happend there for this particel with this spin/speed/direction/info was changed to mass in this black hole.
5. Thanks for the video. The sound recording really needs some work, though.
6. (K Boltzmann * (( Area of black-hole/Planck area)/4) * c^3)/(4G* h-bar) = S (thermodynamic entropy)
   
   If this is correct formula, is there a way to get this in a picture format that can be copied and pasted.
7. Very nice .
   Just that the sound quality is horrible - you can barely hear him...
   Thanks for uploading! :)
8. It's very cool that this is made available for free and I don't want to sound like a jerk but I know I'm not the only one on here that wishes he had a mic on his shirt or something to reduce the class echo and perhaps a better view of the chalk board lol.
9. I love guessing what is written on the board o_^
10. Rovelli and Vidotto publish on “Planck stars. An elegant solution to the information paradox.
    https://medium.com/p/6cf7ec0ed28b
11. Unique horizons
    
    Putting the notion of virtual-micro black holes and virtual-Hawking radiation aside for a moment...
    
    Why is it not the case that when Alice crosses the horizon as observed from an outside observer, she isn't actually at the singularity?  Or, from the perspective of Alice, that when she's hitting the singularity, she's not actually hitting the horizon and getting reflected back into the universe?
    
    If we say that someone in a spaceship is traveling near c experiences less time from their perspective, and that someone on Earth experiences more time from their perspective, we don't assume that the guy flying in the space ship experiences real time while Earth is observing an illusion. 
    
    This seems to mean that there could be no physical singularity, this is just information processing due to a 2-sphere, not unlike any gravitating body that has no event horizon (unless you assume that fundamental particles are  somehow ultimately composed virtual-micro black hole or that the vacuum houses flip flopping virtual-micro black holes and virtual-Hawking radiation).  We think Alice falls through the Horizon and redshifts away, where she continues to fall to hit some singularity.  But we now know that there could be a firewall, which is being debated.
    
    It just seems to be the case that Alice's horizon is not the same horizon that outside observers observe.  There is no time simultaneity nor is there any spacial simultaneity.
    
    It might be the case that the time and radius coordinates swap just for mathematical reasons.  Or that time is using the radius coordinate because Alice is being reflected into the future once she crosses the horizon.
    
    If her information is being scrambled up and preserved, then bits of her that cross the horizon are in fact going into the future by some measure related directly to the mass of the black hole since that determines the radius.  And if the time coordinate then because spacial, then as time passes to an observer outside the horizon, Alice's spatial coordinates as Hawking radiation increase.
    
    In this sense, the singularity for Alice's bits are at the point where her Hawking radiation is fully ejected and spread back out of the horizon into the Universe.
    
    +Joe Polchinski +Juan Maldacena 
12. Quick comment -- not much on firewalls here, a better title would be "Black holes, Entanglement and Worm Holes" Either way, it is Lenny at his best.
13. Thank you so much for the videos from this conference. By the way, in response to a previous post, I have no trouble of a 40" screen getting almost everything of the blackboard w/o difficulty. And I actually prefer the full bb, rather than attempting to focus in on one or another section. Obviously, it would be great if you had n camera persons, but since you are just setting up a tripod and getting a single view/zoom ... this is pretty fine by me. Again thanks and keep them coming!
14. I like the way he films it it gets the whole shot.
15. Is the owner of this channel are filming this? Please stop it, for the sake of Susskinds awesome lectures. You ruine the whole thing, the sound is bad, it's not focused on the blackboard(which is the most important thing). Please find some other guy with good equipment and a brain in his head. I wouldn't survive it if another awesome lecture like this get screwed because of this stupid guy.
16. Helps a lot if you watch it in an external viewer and boost contrast, brightness and gamma.
17. The camera should focus on the blackboard, not on the whole room.
18. Love susskind..,also I think I took linear algebra in that classroom
19. very exciting to see this so soon, good job, can do even better! Sound gets better, and the subject is made very understandable and delivered with a degree of philosophy- the presenter seems to be having fun.
20. And blackboard is illegible.