Hawking's maths exist, maybe not as you know it, but exists it does, in a form he can readily make available to his peers. Plus he worked on his earlier papers with such noted reputables as Thorne, Hartle and Roger Penrose. To say his earlier papers did not show mathematical validity is false. The last paper [the topic of discussion] did not delve into the maths and is one of the reasons why his peers are treating it very critically. In any case, the title of the thread, like the article is just sensationalism, and once again, BH's their EH's, the aspects of time, past present and future all have their reality when speaking of the Universe, expansion, space/time, FoR's and BH's EH's. The 20th century has been great for the cosmological/Astrophysical sciences, and we have discovered/realized much, although much more is around the corner waiting.......But the probability remains that the BB, SR/GR and their spin offs are so well supported, that the future will no doubt encompass them, with only some tinkering around the edges maybe.
Where is Hawking wrong? It seems pretty basic to me. He discovered over 40 years ago that the black hole in our universe isn't the classical object derived by GR. The quantum nature of the black hole is NOT IN the GR domain of applicability. Think in terms of theoretical models. For example Maxwell's equations are a classical model of electromagnetism while the standard model has two quantum theoretical models of electromagnetism. It's expected that a theoretical model of quantum gravity will be found. So he predicts there is no firewall, they're apparent horizons, and that the classical description of the black hole doesn't describe everything we know about the black hole. It used to be the only thing we could know about the black hole is M, J/M, Q/M. Now we have to include what we know about the quantum nature of black holes. The key thing he talks about is the stuff about the 'information paradox'. He's been having fun with that since he discovered black holes radiate. Hearing the nonsense about his lack of mathematics and doting old age is beyond stupid. He's been doing that, in his head, ever since he started getting worse. Dudes a freak of nature and if folks don't know what physics he's done they should put a cork in it until they find out. Especially those who post equations in public science threads that can't even get dimensions right.
Not as basic to me brucep, but I do see your point and agree with the rest of the post..... Did you see this? http://www.universetoday.com/108870/why-hawking-is-wrong-about-black-holes/ where it says, " But the firewall paradox only arises if Hawking radiation is in a pure state, and a paper last month by Sabine Hossenfelder shows that Hawking radiation is not in a pure state. In her paper, Hossenfelder shows that instead of being due to a pair of entangled particles, Hawking radiation is due to two pairs of entangled particles. One entangled pair gets trapped by the black hole, while the other entangled pair escapes. The process is similar to Hawking’s original proposal, but the Hawking particles are not in a pure state. So there’s no paradox. Black holes can radiate in a way that agrees with thermodynamics, and the region near the event horizon doesn’t have a firewall, just as general relativity requires. So Hawking’s proposal is a solution to a problem that doesn’t exist. Read more: http://www.universetoday.com/108870/why-hawking-is-wrong-about-black-holes/#ixzz2sDXAPiCT ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: I'm open for interpretations on the above.....The obvious problems existing in this debate is the usual....Someone with an agenda sees a sensationailist headline and jumps on it, then some other goose feels like questioning other aspects of GR and time. Don't get me wrong.....I have all the time in the world for Hawking [I have said that] and have two of his books. What you say about him is absolutely true in spades. I also accept the quantum theoretical issue and is the reason I posted the link. In essence its another storm in a teacup thread, raised by another closet anti mainstreamer cynic.
The authors lose me when they claim that aliens in a far distant part of our universe can see our future, even though we can't see it. This smacks of lack of free choice, and I would venture violates the uncertainty principle. But thanks for finding the video, though I know you weren't searching it out for me, even though anyone who lacks full knowledge and wisdom can be said to be in a confused state (such as Hawking!).
I note you've shifted the discussion away from Schwarzschild coordinates. Do you concede the four points I raised in [POST=3157433]post #98[/POST], including the fact that elevating the Schwarzschild coordinates to a privileged status is fundamentally in conflict with the principle of general covariance that GR is based on? While changing the subject, you also fail to acknowledge that: 1) A black hole can very well be in an outside observer's causal present (which isn't trivial: not everything is in an observer's causal present). 2) While we don't have global inertial reference frames in GR, it is always possible to associate locally inertial reference frames to inertial observers. These are coordinate systems that, over a limited range depending on the curvature, have approximately the same characteristics as SR inertial frames. An inertial observer just outside a black hole could very well call some of the inside of the black hole "now", and be just as justified in saying so as you would be if you talked about the sun being in some particular state "now". You're still not getting this. There is no inertial frame from Earth period. Strictly, there are no inertial frames in GR in any situation where the spacetime curvature isn't exactly zero everywhere. There is nothing special about black holes in any of this. So if this is a criticism, you're not criticising black holes at all here. What you're really doing is criticising all of general relativity for not being special relativity. That is not an accurate summary of anything I explained to you at all. I really don't know what's worse here: that you've understood so little of what I've tried to explain to you, or your false confidence that you have understood any of it.
The authors being Greene, Tegmark and Carrol... Please Register or Log in to view the hidden image! and it wasn't as straight forward as you express and try and have us to believe. Obviously you are being rather silly in inferring Hawking is in a confused state, or ever has been for that matter... At this time, I'll stick with the mainstream...seems to be far more confusion from those outside that arena than encompassed by it. Please Register or Log in to view the hidden image! I think I have left my self open with that last comment....I can hear it now, "bloody mainstream cheer leader!"
All in all, such a flurry over a non event virtually.......Again the storm and the tea cup come to mind. Please Register or Log in to view the hidden image!
actually, it was. they were very explicit that aliens can see our future, even if we, in our FoR, cannot. Maybe they didn't mean it? But that is exactly what their video claimed.
Hawking showed the firewall couldn't exist as real natural phenomena. GR doesn't predict any quantum phenomena. Nada quantum phenomena since quantum phenomena doesn't exist in the GR domain of applicability. If we didn't think quantum gravitational phenomena exists then we could just believe that GR is the final word about gravity in all domains. But that's not the case and Hawking, Hartle, and Jacob Bekenstein provided the first reasons for beginning quantum gravitational research. Since then I've been interested to see if they could devise an experiment to confirm radiation associated with horizons. Hawking radiation. Check this out from William Unruh. Has Hawking radiation been measured? http://arxiv.org/abs/1401.6612 Hawking radiation from "phase horizons" in laser filaments? http://arxiv.org/abs/1202.6492 This is the experiment Professor Unruh is referring to Hawking radiation from ultrashort laser pulse filaments http://arxiv.org/abs/1009.4634
Personally as a layman, and always thinking Hawking Radiation was indeed a goer, based on simple logical scenario and conservation of energy, I did not know there was any supporting evidence at all. I have learnt something to chew on tonight...Thanks. The rest of your posts makes sense also, just a pity there were a few distractions and excess agendas to overcome. Please Register or Log in to view the hidden image!
This leaves a degree of uncertainty. Here are a couple of examples: "FIG. 1: The sound waves emitted by a yelling fish as it goes over a waterfall which goes supersonic at the red line. Just as for a black hole, beyond the sonic horizon, the sound waves are swept over the falls with the fish. (Note that the appendages on the heads of the fish are ears, not fins, since these fish experience the world through sound, not sight." and "Thus, this experiment give strong support to the hypothesis that horizons, whether black hole, sonic, or other will produce a quantum noise with a thermal spectrum, whose temperature is determined by the behaviour of the horizon." quoted from: http://arxiv.org/abs/1401.6612
The thing that I find most fascinating is the marriage between theoretical and experimental physics. Since it's really interesting I'll copy paste William Unruh's abstract submitted January 26th. "Has Hawking radiation been measured? W.G. Unruh (Submitted on 26 Jan 2014) It is argued that Hawking radiation has indeed been measured and shown to posses a thermal spectrum, as predicted. This contention is based on three separate legs. The first is that the essential physics of the Hawking process for black holes can be modelled in other physical systems. The second is the white hole horizons are the time inverse of black hole horizons, and thus the physics of both is the same. The third is that the quantum emission, which is the Hawking process, is completely determined by measurements of the classical parameters of a linear physical system. The experiment conducted in 2010 fulfills all of these requirements, and is thus a true measurement of Hawking radiation." Another thing I've wondered is will Hawking-Hartle-Bekenstein be considered for the Nobel prize in physics if the Hawking process is experimentally verified?
I'm surprised no one has brought up analogous black holes, which in themselves prove that such systems and such radiation is possible, if not highly probable.
Thin gruel, przyk. Coordinate systems are artefacts of measurements, they don't actually exist. Especially one that puts a stopped observer in front of a stopped clock to hoppity skippity jump to the end of time and back. To assert that this is just as good as my coordinate system isn't adhering to the tenets of GR. It's a failure to recognise non-real solutions. It's cargo-cult science. NB: you will be aware that Kevin Brown's article used to quote Wheeler rather than Einstein. It would seem that MTW is a part of the problem.
RJ: I don't think you've got the hang of this black hole event horizon yet. It's pretty simple IMHO. Try this: Imagine you're a water molecule floating around in the upper atmosphere. Near to you there's a small, hailstone similarly floating. You find yourself subject to electrostatic attraction, and you alight on the surface of the hailstone. You do not pass through the surface. It is frozen solid. You will never pass through this surface. Not in a billion years. However within a minute or two, other water molecules join the hailstone, and soon you find that you are buried within it, frozen solid with those other water molecules. You did not pass through the surface. Instead the surface passed through you. The event horizon is the "surface". You can't pass through it, but a black hole can still grow.
I glad I'm not the only one to have noticed that. That's why I called him an old Newtonian, for holding that the distant observer's coordinates are absolute in respect that nothing reaches and crosses the event horizon. That this is RJ's reasoning is from his post... So, RJ is totally ignoring the in-faller frame of reference. ~~~~~~~~ I'm glad you said that too. After reading your posts and then reading RJbeery's post saying you agree, I begun to get doubtful of my comprehension of this thread. ----------------- Asked this earlier of folks ...One thing I notice about the quantum interpretations of the EH, is that to me, nothing has been said about an in-faller being stopped at the EH (why should they be?), only that the in-faller is fried, the mass still goes through and the BH increases in mass. Does that make sense at all?
This is an excellent analogy in explaining your understanding Farsight. Where I would differ on this is that the hailstone never freezes in the first place, but gets asymptotically close to freezing at its center as more and more water droplets accumulate around it.
Nimbus: RJ isn't ignoring the infaller's frame of reference. Kruskal-Szekeres coordinates have a schoolboy error to them wherein you put a stopped observer in front of a stopped clock and claim that this observer sees the clock ticking normally. He doesn't. He sees nothing. I've been through this with przyk before. He'll go quiet on us now because he has no adequate response to this inescapable upshot of infinite gravitational time dilation at the event horizon.
Thanks. I hope my understanding helps to bridge the gap between your understanding and the evidence that black holes do actually exist. No problem with that. The frozen-star black hole is a bit like a hailstone going to 0 degrees Kelvin rather than 0 degrees centigrade. Only what we're really talking about is the coordinate speed of light going to zero. You maybe can't quite get there, and you definitely can't get below it. You'll be aware that the local force of gravity relates to the local gradient in the coordinate speed of light? Since you can't have a coordinate speed of light that's less than zero, there's no force of gravity at the event horizon.
I actually like that analogy, although I don't believe you can write off passing through the horozon....I see it as a matter of where one chooses to look at it. Sort of like deciding if something is actually pushing or pulling, in relation to that silly argument claiming there is no pull only push.
