Stephen Hawking's Hairy Black Holes: Paper Published on Information Paradox - Polidicks

[b]The 'Soft Hair' on Stephen Hawking's Black Holes[/b] [quote][b]The subject of the paper is a deeply vexing problem known as the black hole information paradox.[/b] This is the conundrum that arises when we ask what happens to information as it falls into a black hole. Does it persist in some form or is it lost? We hope that it persists in accordance with the rules of quantum physics, which demand that the probabilistic information governing a quantum state not vanish, but that sure doesn't seem to be the case. Before going on, let's restate the information paradox question in maybe more stark terms: Does there always exist a history? If there is a present, is there a past? If information can indeed be lost, well, then we can imagine something that exists but without a history. Now, pause here for maybe five or 10 seconds to imagine a universe in which history itself is routinely gobbled up. Like in the Stephen King's The Langoliers. Anyhow, [b]Hawking doesn't have an answer to the information problem, but the new paper offers a tentative step toward an answer. This is where hair comes in.[/b] Around 1973, the physicist John Wheeler declared that "black holes have no hair." The phrase is the origin of what came to be known as the no-hair theorem or no-hair conjecture. What it states is that black holes are essentially bald, or featureless. From the outside, they can be characterized by three parameters: mass, electric charge, and angular momentum. But nothing else. If you were to have two black holes with the same mass, charge, and momentum, but one of them consists of antimatter and the other consists of regular matter, they would be completely identical. The same black hole, really. In the new paper, Hawking gives black holes hair. [b]These are minute deformities in space-time that may exist around the event horizon of a black hole in the form of "super translations."[/b] The idea is that as a charged particle passes the threshold of a black hole, its information is stripped away and left just outside. The super-translation occurs as the incoming information jiggles the fabric of space-time a tiny bit, but enough to influence the radiation being emitted by the black hole. Don't imagine this radiation as little blips of light. (That's how I usually think of radiation.) Imagine itself as individual rays of light blasting outwards at the speed of light. They're going at the speed of light, for sure, but right here at the boundary of a black hole they're sucked backwards with just enough force to make them seem to be just lingering there frozen at light-speed. This is why you can't get out of a black hole. Nothing is faster than light! .... [/quote] [t]http://motherboard-images.vice.com/content-images/contentimage/29456/1452401814638389.jpeg[/t] [url=http://motherboard.vice.com/read/the-soft-hair-on-stephen-hawkings-black-holes?utm_source=mbfb]source[/url]

That black hole is clearly yellow. These physicists don't know what they're talking about.

[QUOTE=SGTNAPALM;49501916]That black hole is clearly yellow. These physicists don't know what they're talking about.[/QUOTE] Maybe they're just really good at bleaching a black hole

I'm too perverted for this

i've always wondered what's inside a black hole? If i where to travel inside such an object and still exist what would i see? If it's swallowing stars/planets will the matter be there, or shot out into space somewhere?

Sixty Symbols did a good video on it recently: [media]https://www.youtube.com/watch?v=I55e6chHUs0[/media] [editline]10th January 2016[/editline] [QUOTE=ridinmybike;49502685]i've always wondered what's inside a black hole? If i where to travel inside such an object and still exist what would i see? If it's swallowing stars/planets will the matter be there, or shot out into space somewhere?[/QUOTE] Matter which has entered a black hole (i.e. passed the event horizon) cannot be shot back out into space. It is doomed to fall into the singularity.

[QUOTE=JohnnyMo1;49502686]Sixty Symbols did a good video on it recently: [media]https://www.youtube.com/watch?v=I55e6chHUs0[/media] [editline]10th January 2016[/editline] Matter which has entered a black hole (i.e. passed the event horizon) cannot be shot back out into space. It is doomed to fall into the singularity.[/QUOTE] maybe matter that is ripped so fast into the hole that the rest of the matter lingers just outside the horizon.

[QUOTE=JohnnyMo1;49502686]Sixty Symbols did a good video on it recently: [media]https://www.youtube.com/watch?v=I55e6chHUs0[/media] [editline]10th January 2016[/editline] Matter which has entered a black hole (i.e. passed the event horizon) cannot be shot back out into space. It is doomed to fall into the singularity.[/QUOTE] I was wondering, usually they say inside a black hole is pretty chill (i.e. you wouldn't really notice at first that you crossed the horizon, disregarding the firewall thing). But wouldn't there be the rest of the accretion disk that's being sucked in be there with you? And wouldn't that generate tons of radiation? So a "dirty" black hole would mash everything that comes to too close (event horizon or not), no?

[QUOTE=Number-41;49506665]I was wondering, usually they say inside a black hole is pretty chill (i.e. you wouldn't really notice at first that you crossed the horizon, disregarding the firewall thing). But wouldn't there be the rest of the accretion disk that's being sucked in be there with you? And wouldn't that generate tons of radiation? So a "dirty" black hole would mash everything that comes to too close (event horizon or not), no?[/QUOTE] Well sure, but that's not really a feature of black holes specifically. "Having a bunch of hot shit floating around" is gonna kill you whether you're near a black hole or not. When people say you wouldn't notice crossing the event horizon, they're talking about a lone black hole in empty space. Of course, since the whole firewall debate is still going on, it's too early to say what would definitely happen as you cross the event horizon, but you wouldn't notice classically anyway.

[QUOTE=JohnnyMo1;49502686] Matter which has entered a black hole (i.e. passed the event horizon) cannot be shot back out into space. It is doomed to fall into the singularity.[/QUOTE] bet i could do it i've been cycling a lot so my jumping is pretty good

[QUOTE=JohnnyMo1;49502686]Sixty Symbols did a good video on it recently: -snip-[/QUOTE] Figured I should also post the extra footage for those who don't want to click on the anotation or can't: [media]http://www.youtube.com/watch?v=ML5zJ0gCE70[/media] [editline]11th January 2016[/editline] [QUOTE=ridinmybike;49502685]i've always wondered what's inside a black hole? If i where to travel inside such an object and still exist what would i see? If it's swallowing stars/planets will the matter be there, or shot out into space somewhere?[/QUOTE] I think you guys either misunderstood the question or understood it, but I think there's a different question to ask. Imagine if you somehow got inside a black hole in one piece without thinking about how you got there. What would you find inside, if anything? The video posted before suggests a theory about 'baby universes' inside them. Would you find all the stuff that went inside the black hole there?

[QUOTE=DeadKiller987;49507335]I think you guys either misunderstood the question or understood it, but I think there's a different question to ask. Imagine if you somehow got inside a black hole in one piece without thinking about how you got there. What would you find inside, if anything? The video posted before suggests a theory about 'baby universes' inside them. Would you find all the stuff that went inside the black hole there?[/QUOTE] I'm not sure if the baby universes concept is different from what I'm thinking of, but certain black hole solutions (specifically, charged rotating black holes) have a bunch of different "universes" attached (regions of space that you can access after you enter the black hole which work like the area outside the event horizon where you started). Maybe. It's quite likely that these weird spacetimes can't come from realistic collapses of stars, as they rely on a high degree of symmetry. But the point is that in such scenarios, they stuff that has fallen in can hit the singularity, or escape to one of the other "universes" or fall into a black hole in one of those other universes and hit the singularity there, or keep going into even more universes. All of those are accessible scenarios for massive matter, but probably not massive matter under its own power. I think the most likely scenario for something that's not a rocket is hitting the singularity.

[QUOTE=JohnnyMo1;49507442]I'm not sure if the baby universes concept is different from what I'm thinking of, but certain black hole solutions (specifically, charged rotating black holes) have a bunch of different "universes" attached (regions of space that you can access after you enter the black hole which work like the area outside the event horizon where you started). Maybe. It's quite likely that these weird spacetimes can't come from realistic collapses of stars, as they rely on a high degree of symmetry. But the point is that in such scenarios, they stuff that has fallen in can hit the singularity, or escape to one of the other "universes" or fall into a black hole in one of those other universes and hit the singularity there, or keep going into even more universes. All of those are accessible scenarios for massive matter, but probably not massive matter under its own power. I think the most likely scenario for something that's not a rocket is hitting the singularity.[/QUOTE] See this basically flips over my understanding of blackholes. My understanding has been 'its basically a neutron star but massive enough to have an event horizon larger than its radius', which prevents light (or anything) from escaping its gravitational pull. Is it not that? (A related question is, can a neutron star have a blackhole beneath its surface?)

[QUOTE=JohnnyMo1;49502686]Sixty Symbols did a good video on it recently: [media]https://www.youtube.com/watch?v=I55e6chHUs0[/media] [editline]10th January 2016[/editline] Matter which has entered a black hole (i.e. passed the event horizon) cannot be shot back out into space. It is doomed to fall into the singularity.[/QUOTE] I still don't really get what they mean by "information" in physics. It always sounds like only relevant to a thinking observer. I'm pretty sure it isn't, bit their analogy made it seem that way.

[QUOTE=Mingebox;49509100]I still don't really get what they mean by "information" in physics. It always sounds like only relevant to a thinking observer. I'm pretty sure it isn't, bit their analogy made it seem that way.[/QUOTE] The way that I kinda understand it is that it is the organization and properties of matter? Like 2 different people on one level could be compared as the same (they are both humans) but on a cellular level will vary (and subsequently on a molecular level will vary, such as different DNA)

[QUOTE=Mingebox;49509100]I still don't really get what they mean by "information" in physics. It always sounds like only relevant to a thinking observer. I'm pretty sure it isn't, bit their analogy made it seem that way.[/QUOTE] The thought experiment I like to use is a little different than theirs. Imagine a bowling ball falls into a black hole. Eventually it hits the singularity, the black hole gains mass, etc. All the stuff they said in the video. Now go back to the beginning of the thought experiment and drop a bowling ball into the black hole from the opposite side. It hits the singularity, the black hole gains mass, etc. You end up with the same final state as the first one, but they came from two distinct physical situations (bowling balls on different sides of the black hole). So if we were to run the laws of physics backwards, how could the universe know which state it started in? It's not encoded in current configuration of matter in the universe, apparently. A black hole reduces the amount of information in the universe. Quantum mechanics has no issue with this. The laws preserve information. If you have a physical situation, you can run the laws of physics backwards to figure out how it started. [editline]11th January 2016[/editline] [QUOTE=Kybalt;49509074]See this basically flips over my understanding of blackholes. My understanding has been 'its basically a neutron star but massive enough to have an event horizon larger than its radius', which prevents light (or anything) from escaping its gravitational pull. Is it not that? (A related question is, can a neutron star have a blackhole beneath its surface?)[/QUOTE] That's almost right, but no, a black hole cannot have a neuron star beneath its surface (at least not in a stable configuration). All matter inside a (Schwarzschild, i.e. uncharged, non-rotating) black hole is forced to move inward and reach the singularity in a finite time. You cannot move outward or even stay at the same radius, everything must fall inward always. But then, as I said in my post before, when you add in charge and rotation, things get weird. The causal structure becomes much more complicated. Your way of thinking about it is helpful, though. An constant-density neutron star with a Schwarzschild radius less than its own radius is just a neutron star. But if the Schwarzschild radius is larger than the radius of the neutron star, you don't have a neutron star anymore. You've got a black hole. The only thing separating them is density.

I can't look it up right now but how come hawking radiation can escape from the EH yet photons cant? [editline]11th January 2016[/editline] although i suppose this was the point of the study

[QUOTE=JohnnyMo1;49509516]The thought experiment I like to use is a little different than theirs. Imagine a bowling ball falls into a black hole. Eventually it hits the singularity, the black hole gains mass, etc. All the stuff they said in the video. Now go back to the beginning of the thought experiment and drop a bowling ball into the black hole from the opposite side. It hits the singularity, the black hole gains mass, etc. You end up with the same final state as the first one, but they came from two distinct physical situations (bowling balls on different sides of the black hole). So if we were to run the laws of physics backwards, how could the universe know which state it started in? It's not encoded in current configuration of matter in the universe, apparently. A black hole reduces the amount of information in the universe. Quantum mechanics has no issue with this. The laws preserve information. If you have a physical situation, you can run the laws of physics backwards to figure out how it started. [/QUOTE] Doesn't the inside the black hole "know" what's inside it? What's to stop it from spitting out the bowling ball if you run the universe backwards?

[QUOTE=Mingebox;49510232]Doesn't the inside the black hole "know" what's inside it? What's to stop it from spitting out the bowling ball if you run the universe backwards?[/QUOTE] The singularity doesn't. It's no longer part of the spacetime, and bowling ball will hit it after a finite time. So if you can somehow run history backwards and get back to your unique initial state, it depends on information which is no longer anywhere in the universe.

[QUOTE=JohnnyMo1;49509516]The thought experiment I like to use is a little different than theirs. Imagine a bowling ball falls into a black hole. Eventually it hits the singularity, the black hole gains mass, etc. All the stuff they said in the video. Now go back to the beginning of the thought experiment and drop a bowling ball into the black hole from the opposite side. It hits the singularity, the black hole gains mass, etc. You end up with the same final state as the first one, but they came from two distinct physical situations (bowling balls on different sides of the black hole). So if we were to run the laws of physics backwards, how could the universe know which state it started in? It's not encoded in current configuration of matter in the universe, apparently. A black hole reduces the amount of information in the universe.[/QUOTE] Well you don't [I]really[/I] have the same final states there; the mass is the same, sure, but the momentum isn't. The difference between the two final momenta states may be negligible, unmeasurable in practice, but in principle it's different.

[QUOTE=sltungle;49510746]Well you don't [I]really[/I] have the same final states there; the mass is the same, sure, but the momentum isn't. The difference between the two final momenta states may be negligible, unmeasurable in practice, but in principle it's different.[/QUOTE] Alright. So make one red and one blue. Or drop two identical particles with opposite spin in one after the other, vs. in the opposite order. I think that's kinda missing the point. It doesn't change the explanation of what information is. Incidentally, [I]can[/I] you distinguish the two final states? In each case the final state is an empty black hole vacuum. So what frame do you measure momentum in, and what quantity are you even measuring? EDIT: Like obviously you CAN do it in principle, everything far from the black hole should work like Newton says, I'm just not sure how you would define it rigorously.

[QUOTE=JohnnyMo1;49510539]The singularity doesn't. It's no longer part of the spacetime, and bowling ball will hit it after a finite time. So if you can somehow run history backwards and get back to your unique initial state, it depends on information which is no longer anywhere in the universe.[/QUOTE] But doesn't it "know" what's going on in it's own space time? Couldn't the inside and the outside only need to "know" their own part of the information and "trust" the other half to put all the particles where they belong? (It's really hard to talk about this information stuff without anthropomorphising things.)