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Stephen Hawking: 'There Are No Black Holes'
ananyo writes "Stephen Hawking has proposed a new solution to the black-hole firewall paradox, which has been vexing physicists for almost two years. The paradox troubles physicists because if the firewall scenario is correct, Einstein's general theory of relativity is flouted. But the classical theory black hole cannot be reconciled to the quantum mechanical prediction that energy and information can escape from a black hole. Now Hawking has proposed a tantalizingly simple solution to the paradox which allows both quantum mechanics and general relativity to remain intact — black holes simply do not have an event horizon to catch fire. The key to his claim is that quantum effects around the black hole cause spacetime to fluctuate too wildly for a sharp boundary surface to exist. As Hawking writes in his paper, 'The absence of event horizons mean that there are no black holes — in the sense of regimes from which light can't escape to infinity.'"
Hawking: ...this means, in a sense, that there are no black holes. Only what I call "Hawking surfaces".
Layman: Does this mean it's possible to travel faster than the speed of light?
Hawking: Sure, why not.
Do not try to reconcile the event horizon. That's impossible. Instead only try to realize the truth. There is no black hole.
Does that mean that he gets his $100 back he lost to John Preskill?
That's it, science has failed once again. I'm going back to christianity.
lol
Oh, sure, easy for you to blather about Mr. Smarter-Than-Einstein AC.
Put up your research, with a name, or shut up.
Scruting the inscrutable for over 50 years.
The event horizon oscillates faster than the speed of light over a greater distance than quantum tunneling can occur. Inbound light would follow the wavefront in, only to become trapped as the next wave built outside its escape range.
Help stamp out iliturcy.
My sense, in reading a considerable number of articles about astrophysics, etc, is that we are in a period which is awaiting the next big breakthrough in knowledge, along the lines of what Newton and Einstein produced. There are still too many unknowns and ambiguities that need to be resolved by discovering a piece of the puzzle which we don't even know exists yet, and I think people are still trying to get their heads wrapped about quantum physics. That said, I'm not a physicist, just an interested lay person, so I may be wrong in that summation, but it seems many of the discussions occurring these days at least pay a backhanded nod to that sort of notion.
In this picture, there would still be astrophysical black holes in every meaningful sense of the word, i.e. condensed objects from which light would not escape. Such objects would have an "apparent horizon", which can be defined locally by the property that all lightlike geodesics are ingoing.
What these black-hole-like objects would not have is an Event Horizon, which is a global property of the spacetime, and is only defined by the behavior at asymptotic infinity. It's a neat resolution of the whole mess: way more sensible than firewalls.
But it's still just hand-waving -- note that the entire argument relies on AdS/CFT, which assumes the black holes are embedded in de Sitter space, which has a negative cosmological constant and is most definitely not the kind of spacetime we live in. And AdS/CFT is itself an unproven conjecture, although it is supported by many specific example cases. Until somebody comes up with a theory of quantum gravity, this stuff is all guesswork. Caveat emptor.
The actual paper can be found here: http://arxiv.org/abs/1401.5761. People have suggested informally ideas somewhat similar to this one before, but Hawking proposal seems to actually have the math behind it. Possibly most importantly, he can show that his predictions are a consequence of gauge/gravity duality http://en.wikipedia.org/wiki/AdS/CFT_correspondence. This suggests that this may be a testale consequence of certain string theories if one could observe a black hole under the right conditions and see that it only was pretending to be a black hole.
It means all these business idiots will stop saying "event horizon".
Proverbs 21:19
Or at least some sort of mathematical proof :)
Seven puppies were harmed during the making of this post.
Data from the satellite orbiting Uranus confirms that the hole is, in fact, brown-ish
To be honest, if anything physicists might have been inventing phenomena, dimensions and particles a little to zealously to explain the math. Scaling it back a little bit is not the same as denying the existence of things that are easily detectable and testable, like cancer, world hunger, pollution, etc. There's nothing wrong with a little mythology - it's normal when you're on the edge of the map pushing back the "Here Be Dragons!" fog. But although some explanations and hypotheses could be dead on, it's unlikely that they all are.
Seven puppies were harmed during the making of this post.
That is an elegant solution that is far more consistent than the "absolute" limits so loved by many. It also points out that our understanding of Quantum Mechanics in reality (as opposed to theory) is pretty incomplete and fuzzy.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
...because he calls them Hawking Holes!
It is better to be the hammer than the anvil.
I've always wondered why there had to be a singularity at the centre of a black hole. Now, it seems, there might not be!
If Hawking is correct, there could even be no singularity at the core of the black hole. Instead, matter [...] never quite crunch down to the centre.
I've been trying to tell people this for years (no, not in a serious crackpot physicist way, just a vague pet idea). Should've tried it with a voice synthesizer...
systemd is Roko's Basilisk.
Newtonian Gravity isn't correct either, we still use it in limited scope. It doesn't mean that Relativity is prevented from the same usage.
But it is still far from correct and the day people finally accept that and move on, maybe some actual research will get done. Dark Matter and Dark Energy are literal blackholes of knowledge that rips Relativity apart in every sense of the metaphor.
There is hardly a contradiction, just you putting meaning where there is none.
You know that building you live in? Built with Newtonian mechanics. That's why it stays up.
And the sat-nav in your phone? That uses general relativity. If it didn't, it wouldn't be able to locate you in the right country, let alone on the right street.
Newtonian mechanics and general relativity have been proven correct many times over. What they are though is incomplete. And there's a mountain of research happening right now to work out why.
No colour or religion ever stopped the bullet from a gun
- Black Hole
Relativity is the most proven theory in the history of science. Nearly every physics major that's graduated in the past 80 years has proven out a different part of it in some new and unique way as part of their doctoral thesis. Every observation that's ever been made that seems to contradict it has later been found to be faulty or explained by some other phenomena that we hadn't understood as of yet.
Infinities exist everywhere in nature. They are naturally hard for us to understand because of our species engrained believe in the Birth/Death cycle and we feel it should apply to everything just well as it does to us.
Lastly, you are correct, Relativity will fail eventually. Even Einstein knew this. It explains "how" things work but only in limited condition and scales. Just like how Newtonian physics worked at the Macro level and at speeds and timescales humans could measure at the time it was devised, relativity only works at certain scales. But it does not invalidate the predictions of Newtonian physics, it just expands them. Eventually we will learn more and there will be a new theory that either explains it all, or at least improves on what Newtonian and Relativistic physics has shown us.
I don't think it is, no. But I do think he overstates his case somewhat. For me, the left eyebrow is raised by the need for huge quantities of "dark matter" in order to account for large scale structure of galaxies even though studies of our local region of space show no such matter exists (or is required to explain it). Now OK, if they discover some WIMPs in future I will hold my hands up, but right now being sceptical is the correct position to take on this. And if WIMPs don't exist, well, the predictions of GR won't match observation so at the very least it will need modification.
This is all notwithstanding the fact that physics simply describes the regularities of experience and apparently gives different answers to the same question depending on how that question is posed. It's still amusing to me that mathematics cannot even deal with the 3-body problem in Newtonian Mechanics adequately without resorting to perturbation methods. Then there's the regularisation issue in Quantum Theory, where infinities magically cancel each other out.
I am not a physicist, but I reiterate the need for scepticism everywhere and at all times. It's possible to be sceptical and also have "wow" moments when physicists come up with genuinely new ideas. I do sometimes wonder just how primitive our current bleeding edge ideas will look to our distant descendents.
Dark matter is required to account for the structure of our galaxy. Sans dark matter, there is not enough observed mass by an order of magnitude in our galaxy to account for the observed galactic rotation curve.
"Unseen matter" is actually the softball bet their, as opposed to the idea that somehow - and nobody really knows or has ever seen how - gravity works differently over long distances. It's just the unseen matter has to have specific properties to fit with observation.
Asimov wrote that great letter - the relativity of wrong.
Any new theory has to account for why the old theory worked for the cases it did. General relativity simplifies at low speeds to Newtonian mechanics for example.
Or from the letter - the Earth is round, but assuming it's flat over short distances is perfectly valid (and we do it all the time - the idea of building level or flat floors for example).
Interesting troll. A bit heavy handed, though. If I were to grade it, if it was written by a high school student it would get a C+, if written by a college student, it would rate a D- (barely passing).
Point of interest: the Copenhagen convention suggests that there is no possibility of a physics Out There. That all physicists can do is make mental models of whatever reality might be, and play around with those models, since reality itself is unobservable without the distortions of observer bias. There are some things we think we know, and there are some things that we know that we can never know (such as what is happening in close proximity to a singularity, or why is Pi 3.14159... and not something else). And it turns out that because there are some things that we know we can never know, we can't be sure about any of the things we think we know.
So, yes, AC is completely correct: relativity is wrong. Also quantum mechanics is wrong. Also classical physics is wrong. It is all wrong. So what? Asking whether this stuff is right or wrong is asking the wrong question. The right questions to ask of any physics model are: How useful is it, and what is its scope of usefulness?
We are the tool using monkeys. We are not Gods. Don't sweat the Really Big Stuff. Do something with the tools: make more tools, make some fun toys and games. That's what we do best. And, that's all that we can do.
Will
Should be easy enough. Find the base discrete unit that measures time (eg the smallest step in time you can make), and the base discrete unit of distance. If the speed of light, measured by those units, is 4,294,967,296, then you're living in a simulation.
You are not alone. This is not normal. None of this is normal.
I always hear about this galactic rotation curve. I understand that there are other observations that seem to point the way to there being extra matter also, but the curve idea give rise to a question I have. Have physicists taken into account that the stars nearer the center of the galaxy are in a deeper gravity well and so will experience time at a different rate than the stars out at the edge. Also, the stars at the edge are moving faster, so they have a speed factor to their local time. If time is changing as you move from the center to the edge, then I would not expect things to appear right to someone who calculates how things should look by some computer simulation if the simulated galaxy has consistent time throughout.
-- ssoorrrryy,, dduupplleexx sswwiittcchh oonn.. -Quote found on actual fortune cookie.
If you add the mass of the egos of those on slashdot, that solves the whole galaxy missing mass problem.
You have no idea what you're talking about. GPS has to be resynced because our clocks are imperfect, the path of GPS satellites is imperfect and there are tiny errors introduced by outside forces like the Earth's electromagnetic field. Satellites fail because we are incapable of building perfect, error-free machines. And quantum entanglement has nothing to do with relativity.
Have physicists taken into account that the stars nearer the center of the galaxy are in a deeper gravity well and so will experience time at a different rate than the stars out at the edge
Yes, but only recently. They have also detected similar rings of gravitational lensing in galactic voids that have no observable matter, indicating huge amounts of invisible matter in areas with no other detectable matter within tens of millions of light years of the locations.
Of course Relativity is flawed. The point is that it's far less flawed than Newtonian mechanics. And that so far nobody has yet managed to come up with something even less flawed. That's called science - there no room for Truth, only successively more accurate approximations.
If you have a better theory, please shareit, but it better be able to explain everything explained by Relativity, plus create entirely new predictions confirmed by reality. Otherwise expect to be laughed off the stage.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
And THAT is hard to explain without dark matter.
The question I have is "Why do they assume that it's simple, and doesn't interact with itself?" Actually, since we're talking about, say, 9/10 of the matter in the universe, why don't we assume that there are 9 non-interacting kinds of dark matter, and that each of those kinds is as diverse as what we think of as normal matter?
Please note, I realize that this isn't in the standard model, but searches based on the standard model haven't been notably successful, so I don't see any reason to believe that it applies.
I know that they think they're applying Occam's Razor, but that's only looking at it in one direction. From another direction since we rarely encounter anything that's homogeneous, to assume that something you can't really see is homogeneous appears to be a violation of Occam's Razor (though, admittedly, not as much a violation as would the assumption of any partiuclar variation). But every time that I can recall when we've assumed that the things we don't really understand are simple and unitary, we've been wrong.
I think we've pushed this "anyone can grow up to be president" thing too far.
So, you think Hawking is attention-grabbing because somebody else said they are, "Hawking Surfaces"? Come on.
Hawking is a well-respected scientist who still does good work in theoretical physics. And this paper is quite good. It is a pretty radical re-thinking of black holes that, if it holds up to further scrutiny, will be considered a very important insight.
I don't think that people will stop calling these objects black holes, but he is absolutely correct in that if this idea holds up, it is a statement that classical black holes do not exist. This doesn't say that extremely dense objects very much like black holes don't exist. But it does say that some of the important, defining features of black holes simply aren't accurate.
look, I don't understand why I have to suck up to Hawking by quoting his resume to you in order to criticize his science
he's a scientist and public figure who presented research...fair game...i know he's a genius & has done great work but **fuck that**
what is THIS theory? seriously read through this thread...so many /.'ers dont even discuss the actual theory or physics or cosmology they just argue about Hawking
I want to discuss the actual research & theory
no, it will be a statement that **Hawking's Version** of Black Holes do not exist...which we already know anyway
Hawking is not the be-all-end-all of black hole research...his cosmology was & still is popular but he's become biased egregiously to his own legacy
Black Holes are bubbles of Quantum Foam. They are the same as what is beyond the horizon of the universe itself. The Event Horizon simultaneously has a quantum entaglement with anything that touches it's surface (the hologram) then all that it was, light, matter, radiation, etc etc. gets turned into the pure randomness of the black hole itself.
Black Holes are truly pure nothingness. Nothing escapes it but the total area of the event horizon expands in relation to the matter/energy that touches it.
Hawking is a genius but he crosses the line of scientific skepticism. He's actually a very biased scientist promoting an agenda. His book a brief history of time has a late chapter where he theorizes that a 'god' could not exist in two of 4 types of universes...one being a universe that ends in heat death. He crosses the line of skepticism into promoting an agenda.
you could defend him by noting that none other than Sir Issac Newton did the same thing...but Newton's reputation and his enduring work are separate things...one is hype one is what matters to this discussion. Newton's theories were **helpful**...I'm sorry that Hawking felt Cambridge crammed them down is throat like dogma but the solution is not to react in the opposite way!
Thank you Dave Raggett
Have physicists taken into account that the stars nearer the center of the galaxy are in a deeper gravity well and so will experience time at a different rate than the stars out at the edge
Yes, but only recently. They have also detected similar rings of gravitational lensing in galactic voids that have no observable matter, indicating huge amounts of invisible matter in areas with no other detectable matter within tens of millions of light years of the locations.
What if the permittivity/permeability constants of that "void" areas aren't that constant as we assume they are?
That would actually be really obvious - you'd get massive discontinuities at the boundary regions where the constants started changing, since ordinary matter straying into those regions would be re-arranged at a subatomic level - atoms flying apart, new ones forming, light being stretched and compressed etc.
Ahhh?? How come? I mean, it doesn't need to be a "boundary region" per se, the "constant" may vary gradually, within a small percentage and over large distances.
And, except for variation of several orders of magnitude that would bring the electron orbits inside the nucleus, why would "atoms fly apart"? Their orbitals would modify spatially, but I imagine the orbitals' energy could still remain the same.
Yes, light may be stretched/compressed in the same manner it happens within a lens. Wouldn't this explain a "gravitational lensing"?
Without knowing the exact nature of the change your proposing it's hard to estimate what the precise effects would be, but needless to say the fundamental constants varying in a consistent manner over a region of space would still produce dramatic effects. Modifying that changes all sorts of energy levels - parallel plate capacitors which are charged to an energy in one region of space are suddenly not in another. They'd experience forces counter-acting the energy change - and that's an ideal system. In an atomic system you'd have atoms which suddenly had to shed excess energy somehow - you'd get huge structures of these which would look unlike anything else in the universe (since it'd be a ghost force not explainable as gravity or conventional electromagnetism).
And it very much would be a subatomic re-arrangement - those constants are involved in every level of physics and chemistry. Changes would not result in "simple" results, you'd get massively emergent effects. But probably most importantly, all of this would happen to visible matter - it would be very obvious because we'd see something which didn't make sense with normal forces. Dark matter is notable because the only thing we see is unusual gravitational attraction, and nothing else.