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Wormholes May Save Physics from Black Hole Infernos

The views expressed are those of the author and are not necessarily those of Scientific American.

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Are black holes surrounded by walls of fire? Does this imply that one (or more) of our most cherished physical principles—and here I’m talking about biggies like quantum theory, the conservation of information or Einstein’s equivalence principle—is wrong? Any may our savior come in the form of wormholes? These are the questions consuming some of the world’s foremost theoretical particle physicists as they argue about potential solutions to what has become known as the “black hole firewall” problem—perhaps the most important paradox in physics since Stephen Hawking proposed his first black hole information paradox nearly four decades ago.

Every black hole has an event horizon. Nothing that moves inside a black hole’s event horizon will ever escape, not even light. Yet we’ve always understood event horizons to be less than dramatic—if you were to cross one, you wouldn’t notice anything immediately amiss.

Event horizons are important, however, for a number of reasons. Consider that according to the laws of quantum mechanics, a pair of virtual particles can jump into existence. Ordinarily, they quickly come back together and annihilate one another, but if the process happens near an event horizon, one particle can get sucked into the hole, leaving the other to drift into space. This implies that black holes radiate particles, a curious fact that Stephen Hawking pointed out many years ago. Eventually black holes lose so many particles that they shrink and die, having spewed their mass out into the cosmos in a stream of Hawking radiation.

Looking at the situation another way, black holes swallow matter—a star here, a wayward astronaut there—then, over time, spit it back out into the cosmos as Hawking radiation. But because information can not be destroyed—only scrambled—the Hawking radiation must contain all the information about the stuff that fell in to the black hole. And the only way that this can happen is if all the Hawking radiation is entangled—that is, every particle’s quantum state co-depends on the quantum states of all the other particles in the Hawking radiation. (Entanglement is a weird and important quantum concept. If you’d like to know more, I recommend this short video.)

Remember, though, that Hawking radiation only exists because a pair of virtual particles popped into existence. One fell in, the other drifted out. These two particles must also be entangled. Unfortunately, the laws of quantum mechanics forbid promiscuous entanglements—a particle can be entangled with its twin, or the rest of the radiation coming out of the black hole, but not both.

And so we have a dilemma. In order for information to be conserved, particles in the Hawking radiation must be entangled each other. But in order to get the Hawking radiation in the first place, these particles must be entangled with the particles falling in to the black hole. Physicists used to think this might be OK, since no single observer could detect both entanglements. But AMPS noticed that a particle coming out of the black hole could be turned around and sent in to the black hole, illuminating the double quantum correlations and causing no end of quantum mischief. To avoid this, they suggest that as the particle crosses the event horizon, the original quantum correlation breaks, producing a burst of energy. The net effect: a wall of fire.

(For more on the firewall paradox, I’d recommend reading Jennifer Ouellette at Cocktail Party Physics, Dennis Overbye in the New York Times, Zeeya Merali in Nature, Caltech’s John Preskill and UCSB’s Joe Polchinski, who first came up with the paradox along with his colleagues Ahmed Almheiri, Don Marolf and James Sully—the quartet now known as AMPS.)

The black hole firewall paradox has caused no small amount of wonder and confusion amongst particle physicists. It appears as though one of our core beliefs about the universe is wrong: Either particles can be promiscuously entangled, leading to quantum disaster (basically no one takes this option seriously; quantum theory and the no-promiscuous-entanglement rule are far too well supported by decades of experimental evidence), or information is not conserved (another non-starter), or black holes have firewalls (even Polchinski considers this a reductio ad absurdum), or… we just don’t fully understand what’s really going on.

And so in an effort to sort the mess out, physicists gathered this week at the Kavli Institute for Theoretical Physics at UCSB to talk over the options. (They’ve been doing a great job uploading videos of all the talks, so if you’re interested in watching smart folks try to hash out knotty thought experiments in near-real time, you can follow along at home.) One of the most intriguing possibilities for a solution comes from Juan Maldacena and Leonard Susskind, building on the ideas of Mark Van Raamsdonk and Brian Swingle. Maldacena and Susskind posit that the solution to the firewall problem may come in the form of wormholes.

Wormholes! I feel like we haven’t talked about them since the ’90s. Basically, wormholes are theoretical objects that connect two different points in space. They’re allowed as possible solutions to Einstein’s equations for general relativity—indeed, Einstein and his colleague Nathan Rosen first discovered wormholes, which is why they’re also called Einstein-Rosen bridges. Unfortunately, wormholes aren’t perfect—Einstein’s equations also imply that nothing with nonnegative energy (that is to say: nothing that we know of) can traverse a wormhole, so they’re not going to make for useful intergalactic portals anytime soon.

Maldacena and Susskind, following Van Raamsdonk, posit that any time two quantum particles are entangled, they’re connected by a wormhole. They then go on to say that the wormhole connection between particles inside a black hole (the infalling virtual particles) and the particles outside of a black hole (the Hawking radiation) soothes out the entanglement problems enough so that we can avoid the firewall at the event horizon.

Note that this requires a profound rethinking of the fundamental stuff of the universe. Entanglement, a deeply quantum phenomenon, is fundamentally wound into to the geometry of the universe. Or, to flip it around, quantum weirdness may be stuff that creates the substrate of spacetime.

Of course, nothing is settled yet. As Maldacena and Susskind write towards the end of their paper:

At the moment we do not know enough about Einstein-Rosen bridges involving clouds of Hawking radiation to come to a definite conclusion…. The AMPS paradox is an extremely subtle one whose resolution, we believe, will have much to teach us about the connection between geometry and entanglement. AMPS pointed out a deep and genuine paradox about the interior of black holes.

And if there’s one great thing about paradox, it’s that their resolutions require radical breakthroughs. The equipment we build for the job may take us to places we’ve never dreamed.


Image from Wikimedia Commons courtesy of  Ute Kraus, Physics education group Kraus, Universität Hildesheim, Space Time Travel, (background image of the milky way: Axel Mellinger)


About the Author: Michael Moyer is the editor in charge of space and physics coverage at Scientific American. Follow on Twitter @mmoyr.

The views expressed are those of the author and are not necessarily those of Scientific American.

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Comments 46 Comments

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  1. 1. Jennifer Ouellette 2:59 pm 08/23/2013

    Ooh, I love me a good firewalls debate. :) Also for more info, can check out my article as well as my blog post, which goes into more technical detail:

    Link to this
  2. 2. Aiya-Oba 5:46 pm 08/23/2013

    Equator (entanglement) of self-contradiction, oneness of pairness, is Nature’s absolute logic.It’s the self-creation principle and unity unit of All in all (from quantum/subquantum entities to Cosmos-Itself).-Aiya-Oba (Philosopher and discoverer of Nature’s absolute logic).

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  3. 3. Simon Says 5:47 pm 08/23/2013

    it’s a thought! I love this stuff! Didn’t we discover minute, subatomic wormwholes inside atoms at the quark level?

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  4. 4. rloldershaw 6:07 pm 08/23/2013

    Actually I think it was on the head of a pin.

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  5. 5. jtdwyer 6:10 pm 08/23/2013

    There’s far too much misinformation here.
    For starters:
    “This implies that black holes radiate particles, a curious fact that Stephen Hawking pointed out many years ago. Eventually black holes lose so many particles that they shrink and die, having spewed their mass out into the cosmos in a stream of Hawking radiation.”

    There are a number of objections to Hawking’s proposal, but even if his calculations are accepted, see
    “A black hole of one solar mass has a temperature of only 60 nanokelvin (60 billionths of a kelvin); in fact, such a black hole would absorb far more cosmic microwave background radiation than it emits. A black hole of 4.5 × 1022 kg (about the mass of the Moon) would be in equilibrium at 2.7 kelvin, absorbing as much radiation as it emits. Yet smaller primordial black holes would emit more than they absorb, and thereby lose mass.[11]”

    Note that only theoretical, unidentified, small primordial black holes could possibly lose mass over time and evaporate – and then only if they did not accrete any other additional matter. Black holes produced by the gravitational collapse of a stellar core would not, between any Hawking radiation and CMB radiation absorption, lose mass, even if they did not accrete any additional matter.

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  6. 6. ec1966 7:46 pm 08/23/2013

    I got myself all entangled just reading this. :)

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  7. 7. rloldershaw 9:10 pm 08/23/2013

    I am delighted to see that Dwyer and I finally agree on something. Above a certain mass, correctly cited as being in the sub-planetary range, primordial black holes do not “evaporate”. Once formed they are fundamental stable “particles” – just a lot more massive than the WIMPy ones.

    More importantly, I know of no physical evidence for, or observations of, the putative Hawking radiation. While theoretical physicists discuss this purely hypothetical notion as if it were scientific fact, it is not. It is pure speculation.

    The same goes for “virtual particles”. You can use them as convenient devices in your modeling, as in QED, but no “virtual particle” has ever been observed. And using these putative entities to explain the Casimir phenomena is dandy, but there are a host of other ideas that also explain the phenomena (just do a search on

    Some of us are getting mighty tired of being subjected to the wannabe kings of theoretical physics prancing around without any scientific clothes. If they cannot make definitive predictions and meaningfully test their pseudo-science, then they would do well to keep all that stuff under wraps until it passes scientific muster.

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  8. 8. m 10:28 pm 08/23/2013

    If black holes were stable you would have no big bang theory.

    To alleviate this problem we must assume on a higher dimension the black-hole came across and instability that then produced the big bang effect we see, and is also the cause of inflation and indeed could show proportional control of how inflation inflated.

    If nothing escapes a black hole, then we must assume no reactions are occurring inside a black-hole, which is clearly untrue.

    If gravity reaches a point where it is stronger than all the other forces, it would by definition enter a new phase of matter, and the forces themselves would have to disappear, indeed become something else as you cant lose energy.

    Therefore at the event horizon, the other forces start to dissolve into a “new force”, which has no effect on information going in and out.

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  9. 9. tharter 11:05 pm 08/23/2013

    There is another possibility which I have not seen discussed, which is that there simply is no ‘inside’ to a black hole, at least in the conventional sense. Or alternatively that the laws of physics simply do not apply within the event horizon in the same way they do in our spacetime. In that case the AMPS paradox goes away (because it is a violation of QM which takes place INSIDE the EH). No rule is broken within OUR Universe.

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  10. 10. rloldershaw 11:21 pm 08/23/2013

    m says: “If black holes were stable you would have no big bang theory.”

    Well now there is a good point. If the observable universe was ever in the totally collapsed state hypothesized by the substandard cosmological fiction, then how did it go “BANG!”?

    Our heroic theorists produce hand-waving just-so stories involving “vacuum fluctuations” and quantum weirdness. None of it the least bit testable, of course.

    Below is a natural reinterpretation of the Big Bang phenomena in terms of real well-observed systems, but on a much vaster scale than people ordinarily consider.

    In this review [ , see "Galactic Scale Self-Similarity" page] of Galactic and Metagalactic Scale phenomena we will discover that the entire observable universe constitutes a nearly infinitesimal region of one Metagalactic Scale object. The galaxies within this region are crammed together at very high densities. Galactic Scale objects are also chaotically moving at high velocities and this indicates an extremely high ambient temperature. The combination of very high temperature and density produces frequent galactic interactions and mergers. The mass spectrum of galaxies is relatively flat, unlike the abundance trends on the Atomic and Stellar Scales, and therefore significant numbers of moderately massive and very massive systems are present. The evidence for an extremely high-energy environment, the presence of substantial numbers of massive galactic systems, and the strong evidence for global expansion, all suggest a reasonably unique analogy to the interior of a supernova shortly after detonation. In this analogy, galactic systems play the role of fully ionized Atomic Scale particles and nuclei under very-high-energy plasma conditions. In what follows we will see that the SSCP analysis leads inevitably to this radical reinterpretation of the standard Big Bang model for the “origin” of the “Universe”.

    Here is what the great Kepler said: “And I cherish more than anything else the analogies, my most trustworthy masters. They know all the secrets of Nature, and ought least to be neglected in Geometry.”

    There is a wonderfully unified new paradigm out there that is as natural as a theory gets and is the antithesis of the untestable pseudo-science they try to force-feed us. Smoke, mirrors and pretzel logic not required.

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  11. 11. thesamthekip 7:10 am 08/24/2013

    Bad article, no editing. This writing contains several basic errors. First it explains that black holes never lose matter or energy. Fine. Then it explains Hawking radiation originates outside a black hole (one particle of an external, spontaneous pair escaping into space as the other particle falls into the black hole). Fine. But to then say black holes lose particles is ridiculous since the Hawking radiation (particle) was never in the black hole to begin with.

    Second, it says that information is never lost. It’s wrong to apply the principle of conservation of mass-energy (equivalence) to organization, which is just another word for information. Entropy or disorder is real and ensures information will decay and be lost. While the amount of energy isn’t lost, any patterns of energy (information) can be lost (disordered) irretrievably.

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  12. 12. David Cummings 11:12 am 08/24/2013

    There’s something I’ve never understood about Hawking radiation.

    The description of that radiation always describes a process whereby a particle-antiparticle pair appears close to the event horizon of a black hole and the particle with the negative energy falls into the black hole (subtracting mass from the black hole) and the particle with the positive energy escapes, so that to an outside observer, it appears that the black hole has just emitted a particle, and gotten lighter at the same time.

    But the part I don’t understand is this: why is it always the negative-energy partner of the virtual particle pair that falls into the hole? Why isn’t it 50 percent of the time the positive energy partner falling into the hole, thus completely negating the effects of subtracting mass from the black hole?

    In other words, let’s just pick an arbitrary number and say for an arbitrary black hole there are one billion virtual particle pairs created at its event horizon every second. Of those particle pairs, one billion particles are going to fall into the black hole and one billion are going to escape. Of the billion falling in, aren’t 500 million of them going to be negative-energy and 500 million positive-energy, completely cancelling each other out and resulting in ZERO mass decrease for the black hole?

    What am I not getting here? Why am I the first person (I know of) to ever ask this seemingly uber-obvious question?

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  13. 13. grandpa 11:44 am 08/24/2013

    Perhaps the very term black hole has created its own perception dilemma. Perhaps a term such as black mass might point in another direction, including missing matter and another force beyond that of light?

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  14. 14. jtdwyer 3:17 pm 08/24/2013

    David Cummings,
    I share your concern re. the general conception of Hawking radiation. As I understand, it doesn’t even ‘matter’ whether it is matter or antimatter that falls into the black hole – the particle that falls in is considered to have negative energy. As best I can determine, there is no justification for considering the ‘ingested’ particles to have negative energy other than it’s presumed that the ‘ingested particle’ ‘disappears’ from the universe – therefore, in order to maintain the conservation of mass-energy, the energy of ‘new’ particle that now persists must be offset in the universal mass-energy accounting system. Therefore, the disappeared mass-energy must have been negative…

    I very recently posted this comment on another blog:
    “However, I have to wonder – shouldn’t it be considered that all virtual particle pair manifestations – anywhere – are condensations of vacuum energy, and that their energy when annihilated is returned to the vacuum? In that case, it seems that the accounting for their energy is either as particles or as vacuum energy. Certainly there should be no issue with any energy ‘ingested’ by a black hole – it’s still considered to exist within the universe, correct? In that case, it seems that any virtual particles that persist should be ‘borrowed’ from the vacuum and that any Hawking Radiation propagated from an event horizon would also simply indicate an identical mass absorbed by the black hole – just like any other matter it ingests. Perhaps this is not consistent with some other established interpretations, but Occam’s razor states that one should proceed to simpler theories until simplicity can be traded for greater explanatory power. In the absence of supporting evidence…”

    It seems to me that the famed quantum interaction of Hawking radiation is a trivial contrivance – if anything at all!

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  15. 15. David Cummings 3:29 pm 08/24/2013

    jtdwyer, thank you very much for the explanation. That clears up a lot for me.

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  16. 16. jtdwyer 3:47 pm 08/24/2013

    The article states:
    “But because information can not be destroyed—only scrambled—the Hawking radiation must contain all the information about the stuff that fell in to the black hole. And the only way that this can happen is if all the Hawking radiation is entangled—that is, every particle’s quantum state co-depends on the quantum states of all the other particles in the Hawking radiation.”

    I agree with ‘thesamthekip’ that the conservation of information is misconceived – although I may be biased since, as a retired information systems analyst, IMO cosmologists have misappropriated the concepts of information, entropy, order and energy. Conceptually order may imply energy in that material bindings localize energy. But even disintegrating matter does not destroy mass-energy – at worst it is dissipated into vacuum energy. To argue that, by obtuse association and extension, information is organization which is energy is nonsense, IMO.

    I can only dismiss all discussions regarding information conservation as misinformation. This is certainly unfortunate, as in recent decades physics has become full of it – and I’m not even discussing dark matter here!

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  17. 17. Cramer 4:25 pm 08/24/2013

    Please consider two points about the particle falling into black hole as having negative energy:

    1) Particles are entangled.
    2) Particle closer to black hole (gravity well) is negative relative to an outside observer (general relativity). [i.e. The math is not in the frame of reference of the particles.]

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  18. 18. jtdwyer 4:34 pm 08/24/2013

    “And so we have a dilemma. In order for information to be conserved, particles in the Hawking radiation must be entangled each other. But in order to get the Hawking radiation in the first place, these particles must be entangled with the particles falling in to the black hole. Physicists used to think this might be OK, since no single observer could detect both entanglements. But AMPS noticed that a particle coming out of the black hole could be turned around and sent in to the black hole, illuminating the double quantum correlations and causing no end of quantum mischief. To avoid this, they suggest that as the particle crosses the event horizon, the original quantum correlation breaks, producing a burst of energy. The net effect: a wall of fire.”

    Perhaps this is the origin of the confusion for string theorists, but in earlier reports all the discussion was about how the firewall concept would violate the equivalence principle. See
    “Such firewalls would violate a foundational tenet of physics that was first articulated almost a century ago by Albert Einstein, who used it as the basis of general relativity, his theory of gravity. Known as the equivalence principle, it states in part that an observer falling in a gravitational field — even the powerful one inside a black hole — will see exactly the same phenomena as an observer floating in empty space. Without this principle, Einstein’s framework crumbles.”

    This issue is not even mentioned here. Perhaps physicists realized, as I had, that there was no violation: any observer falling into a black hole would see the same dimensional phenomena as an observer floating in space – if only he hadn’t disintegrated!

    The crux of the matter is that physicists seem to be simply entertaining themselves with an unexpected wrinkle in a house of cards – information conservation requires entanglement requiring wormholes… There is literally no predicting where this might end, since it’s unlikely it will ever be decisively resolved, except in the minds of theorists.

    In the meantime, more crucial issues continue to be ignored. Forgetting these perceived issues with paltry few vitual particles that might be materialized as Hawking radiation – what happens to all the matter that initially forms a black hole, and the stars and gasses that are ‘ingested’ later? We know that stars slightly larger than the Sun produce initially hot neutron stars, composed of matter as dense as atomic nuclei – what happens to matter processed by a black hole? Nobody seems to know!

    No – please – not the wormholes again! Please see comment #11…

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  19. 19. gesimsek 4:53 pm 08/24/2013

    In the begining, there was light, ie., massless vacum energy entangled with itself by particle/wave duality without time and space. Then, at some point, they call Higgs’, it started to gain mass at various places, where the time also started to click. In places, where mass became too heavy to allow particle/wave duality, light was frozen in yet to be discovered place.

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  20. 20. Cramer 5:08 pm 08/24/2013

    jtdwyer said, “This issue is not even mentioned here.”

    Yes, it is. Author wrote, “For more on the firewall paradox…” and gave the link to the article you referenced.

    You seem to have a disdain for physicists because they have not figured out everything. You must really hate Isaac Newton because he did not include general relativity in his law of universal gravitation.

    “What happens to matter processed by a black hole?” You could ask the same question by asking if a black hole has gravity.

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  21. 21. Bill_Ellis 9:45 pm 08/24/2013

    If we think of Black Holes as as nexus between two multiverses that could account for the inconsistencies in observations.

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  22. 22. rloldershaw 9:58 pm 08/24/2013

    I am astonished!

    Dwyer is now sounding like a far better scientist than most of the preening celebrity physicists mentioned in the firewalls/wormholes debate.

    Many of the most basic and oft repeated assumptions/arguments of postmodern theoretical physics constitute a house of cards, and the cards are mostly jokers.

    Robert L. Oldershaw
    Discrete Scale Relativity/Fractal Cosmology

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  23. 23. Dr. Strangelove 10:16 pm 08/24/2013

    There’s no paradox here. Only a confusion in the mind of some physicists. Information is not conserved. It can be destroyed. For entangled particles, information does not even exist until you observe it.

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  24. 24. macsj 6:02 am 08/25/2013

    I think we have two major problems here and they deal with accepted but unproven ideas.
    1. Information is conserved.
    2. That a theory that contains a paradox can be true.
    #2 First. A solved theory can’t contain a paradox, because it contains a paradox it is false. We produce the paradox from an unknown variable or a math that almost works. So, I ask are there any paradoxes found in our observations? I might not be informed properly but I can’t find a paradox outside the mind of man.
    #1. See #2. Our physics completely break down in a singularity. We can’t explain the physics inside a singularity, but we produce ideas like “The conservation of information”. With the findings on Higgs we find it does not follow the Standard Model.
    The conservation of information can’t survive a singularity if only because as the conservation of energy states energy can neither be created or destroyed, but it can be changed.
    So a singularity has the potential to change matter and energy forms. Matter to energy, energy to matter. Send a photon pair into a singularity and I think it will cease being a pair.
    Maybe a new physics will be able to explain the possibly of interactions in a foamy multiverse.
    I have always found the multiverse highly improbable because it requires infinite space and energy. Again I find the idea of infinite something improbable. I can create paradox with the infinite. So I have always held that although theories using infinity can seem valid, they lose that validity without man’s mind creating the unobserved infinity.
    I find absolutes only in the mind of man.

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  25. 25. rloldershaw 10:28 am 08/25/2013

    Aristotelean reasoning will lead you to correct answers about 50% of the time, and lead you to wrong ideas about 50% of the time.

    Scientific reasoning based on physical evidence, predictions and testing will get you much farther on the path to an accurate understanding of nature, and help you to be less often diverted into an intellectual cul de sac.

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  26. 26. c laird478 10:37 am 08/25/2013

    Interesting that they say that information cannot be destroyed, yet they claim that they destroy information in the delayed choice quantum eraser double slit experiment. OK, which is it?

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  27. 27. SteveinOG 11:50 am 08/25/2013

    Purely as a matter of idle sci-fi speculation, the large scale structure of the cosmos appears like a foam with matter stretched out between expanding bubbles of empty space and that these bubbles are generated by the matter compressed to infinite density inside black holes and released as vacuum energy (or un-black hole) some great distance away. Thus the universe expands as matter is consumed. Unprovable, but fun to speculate.

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  28. 28. knightshold 12:24 pm 08/25/2013

    I think this wormhole idea is promising, but doesn’t go far enough. I think black holes in our universe are white holes in a parallel universe(s). I think parallel universes are entangled. Practical experiments I have performed convince me that socks are particularly prone to entanglement, and just jump to a parallel universe. Keys are also prone to this effect. We all know that keys disappear every so often. We look everywhere, and they are gone! But just gone from our universe. They wait in the parallel universe for a while (like 15 to 30 minutes, but sometimes days) and then return, usually to the exact spot where we left them and searched a dozen times. Socks display a more perverse phenomenon. They tend to disappear for weeks. Once we have given up on finding a mate, and discard the seemingly mateless sock, it’s partner shows up in the wash. The problem most physicists have is that their thinking is too abstract, studying sock and key related phenomenon is beneath them, and they go through life like a Mr. Magoo spewing forth HAwking radiation in the form of socks, keys, and other paraphernalia. This quantum observers of Physicists usually describe them as absent minded professors.

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  29. 29. And Then What? 5:42 pm 08/25/2013

    Since it would appear that it is currently impossible to measure, in any fashion, what is happening beyond the event horizon surrounding a singularity all that remains is speculation based on measurable events on “our” side of the EH. The conclusions we draw therefrom may simply be erroneous since there is no way to know if Space-time maintains its identity in any recognizable shape or fashion on the other side of the EH. What is more likely is that the rules change dramatically the closer you get to the singularity so that there is no “one” set of Laws that govern the interactions of Energy, Matter and Space-time in a region where the dominant force is produced by an evolving Singularity.

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  30. 30. Zephir 6:50 am 08/26/2013

    The firewall poses only theoretical problem (coexistence of two mutually dual theories), not the phenomenological problem, as the objects routinely evaporate into accretion radiation during their fall into black hole due the so-called [spaghettification]( and nobody is surprised with it. From this perspective we have no problem to solve with wormholes, as the firewall routinely happens around event horizon.

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  31. 31. David Cummings 9:25 am 08/26/2013

    SteveinOG, I would choose a slightly different description (one presented by Brian Greene, among others), that the large scale structure of the cosmos appears like a foam with a vast eternal inflation of truly empty space filled with bubbles, each bubble being a big bang universe (of which ours is one of an infinite number).

    Not a big difference from your description, but just one I prefer. And as you say, unprovable, but fun to speculate.

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  32. 32. PMK4407 12:12 pm 08/26/2013

    A little nit to pick with Mr jtdwyer and rloldershaw. If the hypothesis of Hawking Radiation is correct (and I share Mr Cumming’s doubts) Solar mass and above black holes would not be stable. In deep time all available matter will be absorbed and the CMB will fall below their emission temperatures. At a CMB temperature of 2.6 Kelvin the moon-mass black hold will start to evaporate, at 59 nanokelvin the solar mass black hole will evaporate. All it takes is time.
    On a related matter, perhaps someone can answer this problem for me. Why are physicists agonising over the proposed Black Hole singularity? We know (from actual observation) that increasing mass density slows time. As the mass density of a collapsing star climbs towards infinity does the time distortion not also approach infinity? Each atom’s width reduction in the star’s diameter should (from an external observer’s point of view) take slightly longer than the preceding one so as far as the external Universe is concerned that ‘infinite’ singularity can never be reached. When your equations give you infinite mass and energy in zero space, perhaps throwing in a new ‘infinite time’ term can cancel them out?

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  33. 33. jtdwyer 1:19 pm 08/26/2013

    Perhaps sometime in the distant future the CMBR will eventually dissipate, BHs will have ingested all available matter and evaporate, assuming Hawking radiation does actually exist in the observable universe.
    However, by that time wouldn’t virtual particles also cease to materialize from the vacuum, thereby preventing Hawking radiation? In any case, it’s the currently observable conditions that are being discussed here…

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  34. 34. jtdwyer 1:37 pm 08/26/2013

    Regarding BH time dialation, at the event horizon of a black hole, the progression of time appears to halt only for distant observers. For those falling toward the event horizon time seems to move at its regular pace, although distant light is extremely blue-shifted and any distant events that are identifiable move along at a really extraordinary pace. If observable, distant stars might be born and die in a few moments…
    In any case, matter falling towards the event horizon would do so at a highly accelerated rate. As you mention, I expect that atoms become so hot that they disintegrate – their then released bound nuclear mass-energy is released and retained, likely within the event horizon, as increased gravitational energy – curved spacetime. The residual dimensional particles of matter (and their relatively trivial inherent rest mass) is routed to the polar jets and ejected at relativistic velocities. I also tried to explain in comment #11. Good questions, BTW!

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  35. 35. Dr. Strangelove 8:46 pm 08/26/2013

    As already stated, the whole confusion lies in the false notion that information is conserved. There is no law of conservation of information. Only mass and energy are conserved. When a pair of particle and antiparticle is annihilated, their information is destroyed. The information does not even exist until you observe it.

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  36. 36. SteveinOG 8:22 pm 08/27/2013

    My dear jtmdwyer, concison is everything.

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  37. 37. SteveinOG 8:32 pm 08/27/2013

    jtdwyer. sorry.

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  38. 38. jtdwyer 11:03 pm 08/27/2013

    Fine – can you suggest some alternative text that would effectively communicate the intended meaning while being more concise? Please elaborate!

    Otherwise, do you assert that conveying meaning is nothing?

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  39. 39. Miroslav 4:09 am 08/29/2013

    This article presenting philosophical ideas supported by mathematical theorems does not fit in physics. Physicists speak that the elemental stable particles are quanta of energy since subatomic particles can release them. One from them is photon and other hypothetical is graviton. They are inside of any matter, so inside electrons and baryons.
    Astrophysicists speak that matter can be compressed and therefore they know three forms of matter according to density, so according to density of bound gravitons and photons in matter.
    The first state of matter is this, as we know it in our world, where structures of atoms create matter. In the universe, this matter is in white dwarfs, planets, moons and others. Every body of the solar system has this structure.
    More compressed structure and so less free space for free moving of elemental particles is in baryons and electrons. In the universe, this form matter is in neutron stars. Their density is approximate the same. We know also this denser form in our world but in particles creating atoms (not in atoms and molecules).
    This form of matter is still not the last one since physicists consider for instance the electron not compact particle.
    The densest forms of quanta of energy are in collapsed baryons. Physicists try to achieve this state by experiments in Large Hadron Collider (creating Big Bang’s first particles). Astrophysicists know this state in black holes.
    Since a black hole is the densest form of matter there must exist subatomic particles in maximal collapsed state. When I pick a neutron then its volume should decrease 10^12 times since the density of a black hole is about 10^12 higher than the density of a neutron star. If this number would not be right, still every physicist say that a black hole has enormous density. If there is enormous density then quanta of energy practically cannot move since there can be no free space in the collapsed baryonic matter to allow bound quanta of energy to vibrate or to orbit. Therefore, there could not exist any space for creating any particles. That is why black holes could not spew “their mass into the cosmos in a stream of Hawking radiation”.
    More in the book “Attraction and Repulsion in the Universe” which primarily explains “mass, dark energy, dark matter and their places in Creation” so in the universe.

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  40. 40. 6:55 am 08/29/2013

    I have read a number of Fred Hoyle’s science fiction works … and a number of old fashioned astronomy books full of large photo plates … in the 1970′s as a school student when I read through the local council library’s Astronomy shelf from end to end. What interests me in relation to this article is the old steady state theory. In terms of this current debate, the question is whether singularities in this universe might be of two types, sink singularities which have black hole type behaviour and absorb particles, and source singularities which emit particles of a specific type and lose mass and quantum numbers thereby. The analogy is to the underlying vector/tensor fields … whatever their dimensionality … and the terminologies thereof. If so, and if the hydrogen nuclei and the iron nuclei are extrema in the potential energy well of the fusion fission curve, why not there perhaps be a possibility of semi stable hydrogen nuclei source singularities and iron nuclei source singularities?

    This might even suggest that the red spot of Jupiter is a sign of some singularity inside, perhaps?

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  41. 41. christinaak 4:07 pm 08/29/2013

    What a mess. Almost nothing is understood about the structure of black holes. The idea that if one were to cross an event horizon one would not immediately find something amiss is absurd. It is virtually certain that any object entering an event horizon would collapse upon entry (if space-time is discrete, black holes have a quantized structure and singularities do not exist. Prediction: Almost everything that is discussed in this blog (including wormholes, Hawking radiation, singularities, etc.) will be consigned to the dustbin of history within the next 50 years. Christina Anne Knight

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  42. 42. shorewood 2:48 pm 08/30/2013


    How is it that a particle falling INTO the black hole can cause its evaporation?

    I have read this contention many times, so I accept that it is true / valid. But, how does it make any sense?

    Can anyone explain it?

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  43. 43. kedarj 10:03 pm 08/30/2013

    [“black hole firewall” problem—perhaps the most important paradox in physics since Stephen Hawking proposed his first black hole information paradox nearly four decades ago.]“Information paradoxes” are born from nil “understanding” of what “information” is in the first place! “Data” [Sanskrit - dhAta - giver]is impinging energy on sensors/sensory apparatus – An image bio-molecule is made of this by sentient life forms. These are tagged/classified/graded on a multitude of criteria. Bio-molecule images of these images are offered to seats of understanding to “measure/evaluate” [Sanskrit and Marathi - mAh iti]translating exactly to “information”. The word “Information” is used by the world today in 2014 vaguely without understanding that it is a “measurerment/evaluation process” of Data. It is literally “food for thought and understanding” for life forms. It is a transient mega process having multitude of many many different sub processes. “paradoxes” and “lllusions” result from recursions in deriving meaning/explanation of data of “reality” of observed phenomena in other words,improper understanding of it.

    Now “phenomena”, and “space” are realities. “time” is conjecture and not a real entity. “time” is a measuring system, a process in the mind. Reasoning goes something like this. Observed phenomenon1 in space coordinate x1,y1,z1. observation_date1. Observed phenomenon2 in space coordinate x2,y2,z2.observation_date2. a)Observed phenomenon2 is same/almost as Observed phenomenon1 b)space coordinate x2,y2,z2 is different from x1,y1,z1 c) date2 the date in which I am alive and capable of observing is different from date1 the date in which I was alive and capable of observing. Now (c) is time – the mother of all paradoxes. It is a measuring system that I the observer have devised. What does it measure? the portion of my total observation capability standardized into some convenient unit of measure that is agreed convenient by my friends/members of species. When our whole understanding mechanism is faced with observed paradoxes and dichotomies such as quantum phenomena, the first place to look is my mechanism of understanding and rule out the extrapolation of time into space and conjecture space-time continuums. Space is outside and time is subjective to me. Can I now dare E=mC2 = infinity?

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  44. 44. kedarj 10:35 pm 08/30/2013

    Famous physicists may have said “God doesn’t play dice”…and “Don’t tell God what he can or cannot do” – I say, “I abhor non sense dichotomies and paradoxes” and things appearing with a bang and disappearing with halos/partial halos into God knows where.

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  45. 45. edprochak 2:55 pm 09/3/2013

    to shorewood

    Think of it this way. Now we know that an electron and a positron when they collide annihilate each other to produce a gamma ray. All of the mass of those two particles yields the energy of the gamma ray.

    So picture a quantum fluctuation that spawns an electron and a positron at the EH. Before the fluctuation, the Black hole had the energy of one gamma ray. After the fluctuation, half that energy escapes the black hole. It doesn’t matter if it is an electron or a positron that escapes. It still carries half the energy of the equivalent gamma ray outside the black hole.

    It is this net ENERGY loss that shrinks the Black Hole (BH).

    As I think about it, two things come to mind:
    1. The event horizon is the point where the escape velocity of the BH equals the speed of light. So if you are falling into a black hole, you are already moving at the speed of light as you cross the EH. IOW, at that point you MAY have already been converted to photons. (Because as far as we know, only a zero rest mass particle can travel at the speed of light.)

    2. Within the BH there is likely only photons (conjecture on my part). Multiple photons can occupy the same point in space. This is in contrast to a neutron star which stopped its collapse because it consists of neutrons which must obey the Pauli exclusion principle. This provides the force to keep it from collapsing into a BH.

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  46. 46. JacobSilver 8:26 pm 09/17/2013

    As the article demonstrates, the status of black holes depends on the behavior of quantum particles. These particles have entanglement, and they spontaneously emerge. But I contend that subatomic quantum particles operate in a system which has no time. If there is no time, an observer in a higher state of organization will see that particle in two places at the same ‘time.’ He or she will see entanglement, which appears as a mystery. But without time there is no mystery and there is no entanglement.

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