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Infinite Time and Hawking Radiation

  1. Dec 17, 2004 #1
    Let's say you decide to walk backwards into a black hole. Everything looks normal at first but as you get close everything is speeding up. When you're really close everything is going extremely fast. As you cross the event horizon, infinite time passes. (I know saying "infinite time passes" is a contradiction but you know what I mean.) So what happens before infinite time passes? How could it end?

    I can think of only three possibilities. Everything starts to fall into the same black hole you are falling into including other black holes until everything falls in at the exact same time. The other possibility is that the universe gets stuck in a pattern which repeats forever. (This can't happen if the universe has an element of randomness tho; Can it?) The other idea is that the universe goes on always changing forever. If it seems impossible to imagine, try imagining an irrational number.

    What do you all think? Any of these impossible? Can you think of a different possibility? (Other than the universe ending instantly at some arbitrary time for no reason :tongue2: )

    BTW: How can you say that anything is ever in a black hole if it takes until the universe ends to be in it? How could Hawking Radiation have occured if there was no matter in the black hole in the first place?
  2. jcsd
  3. Dec 18, 2004 #2

    Firstly, there are Three Horizon Paramiters to consider?

    Lets consider what you stateLet's say you decide to walk backwards into a black hole.

    The Direction in Time WHERE you are coming from will be paramount as to your interaction of Event status. Walking backwards will not have any effect, its the direction paramiter that is important, for instance you are coming from the Present Space-Time, BUT..the Singularity you are Heading towards has to be PAST-TENSE, this corresponds to Frozen locations at the event horizon, you CANNOT cross from the Present-Tense to the Past-Tense! The singularity by default is always the pre-fabric of Our present spacetime.

    But for Particles that can skip across dimensional bounderies, such as Tachyons, may move from the future to the past via the present spacetime, but these would occur at the Horizon of a BLACKHOLE.

    The horizon of a Galactic Blackhole for instance permits particles to scatter of Matter(ordinary present phase matter), that has been Parametrically Downconverted. The simplistic fact is that Matter infalling from the present surrounding spacetime at Galactic Cores, is 'FROZEN', or decelerated.

    The interesting thing is that Particles that are emerging from a Galactic Blackhole are technically emerging from the PRE-PARTICLE soup, or Anti-Matter. The high Positron Fields around Glactic Cores are 'past-particles', hawking radiation is the backscattering of Time-Energies, and not Space Energies.

    Every single Glactic Singularity, are Anchor locations for Universe Structures.

    As you cross the event horizon, infinite time passes. Dynamically, Frozen Matter at Horizon is not Time dependant, Time does not come into the equation, Dirac Fields are Phase Dependant. Anti Matter of our Galaxy for instance, is not the same as the Anti-Hydrogen produced in places like Cern.

    For two Galaxies that collide within the Universe, the Anti-Matter/Positron core's, are of different Times, so the interactions give rise to Heavy Particle interactions, so their Horizons can interact and produce a single Galaxy that has matter of a different Phase, two 'OLD' galaxies can Produce a single 'NEW' galaxy!..for all intensive purpose, the new Galaxy can be deemed to have been just created, with Stars that are of different elemental make-up of whats in our Galaxy.

    Black holes are Dynamical, event Horizons for every Galaxy are really distinct for each seperate Galaxy, and therefore Spacetimes are Galaxy dependant.

    The Universe has many Time parimiters, born out of the fact there are multiple Galactic Interactions, each interaction alters the Time Factor for the Galaxies that are interacting, changing and evolving the Matter content of the said Galaxies, Old Galaxies become New Galaxies, with their Stars reconfigured into varying stage's of evolution. A good example is when two Galaxies collide, one that contains Stars that have evolved in a Galaxy that has not had any interaction with another Galaxy, and another Galaxy that has had many recent interactions.

    When these Galaxies collide, there would be a high amount of Stars that switch their Elemental make-up, example Neutron Stars, Quark-Stars interacting with Older Stars, Red-Giants and Heavy Elemntal Stars. The collision would cause a vibrant array of varying Stars. Observing these interactions form our Galaxy would cause problems for standard cosmic model evolution, according to our perception of Universal Time.
  4. Dec 19, 2004 #3
    Wave's Hand Particle, I don't really know what you're talking about. I don't understand why you talk about stars, galaxies, or tachyons.
    I know that the way I'm facing doesn't matter and what do you mean by a blackhole being PAST-TENSE?
  5. Dec 19, 2004 #4


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    The root of the problem is the idea of "walking" into a black hole, IMO. This is something that can't actually be done, though it can be approximated if you have a rocket ship with unlimited acceleration capability, and an ability to tolearate extremely high accelerations.

    If you are inside 1.5 x the schwarzschild radius of a black hole (a region that's also called the photon sphere), you MUST accelerate away from the black hole in order to avoid being sucked into it. Orbiting a black hole inside the photon sphere is not possible - furthermore, attempting to orbit the black hole will only require you to accelerate harder.

    As you get closer and closer to the black hole, your proper acceleration approaches infinity. (The proper acceleration is what you feel).

    Hence the need for a very high performance rocket ship, and the ability to withstand high accelerations.

    Entering a black hole in this manner, you would experience the "time slowing down" phenomenon. And you'd be able to watch the universe evolve, if you could avoid being fried by the blue-shifed energy. But basically, you could experience much the same thing if you just had the super-capable rocketship, by using it to accelerate to hyper-relativistic velocities. You are postulating (without, probably, knowing it), a rocket ship capable of _inifinte_ acceleration, to be able to stay exactly on the event horizon.

    If you enter a black hole in the normal manner, by free-falling into it, you will not get to see the universe evolve - you will not see all of time pass by.
  6. Dec 20, 2004 #5
    When I said walking backwards it was kind of a joke. All that matters is that you are looking opposite to the black hole.
    Can you elabourate on why I wouldn't see the universe go by when I fall into a black hole in the normal manner.
  7. Dec 20, 2004 #6


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    There's a reasonably good explanation of what you see falling into a black hole online in the sci.physics.faq


    As always, "why" you see what you see is a bit tricky to answer.

    If you can find a good "Kruskal diagram", and stare at it for a while, you can answer a lot of questions about who sees what - Kruskal diagrams have the property that light always travels on 45 degree lines. Unfortunately, while there are a few Kruskal diagrams on the WWW, they aren't labelled well enough to be able to figure out a lot by looking at them. Penrose diagrams are also useful for the same purpose (though they are not as detailed as Kruskal diagrams).

    I would highly recommend Kip Thorne's book on black holes, "Black Holes and Time Warps: Einstein's Outrageous Legacy:


    There's probably one point I should clarify a bit. I was talking about what you'd see falling past the event horizon of a Schwarzschild black hole. This does not include the part of the journey beyond the event horizon.

    The theory of what happens when one falls beyond the event horizon are still being investigated, especially in the case of a rotating black hole. There are many issues involved, the stability of the solutions to Einstein's field equations chief among them. Solutions exist in which one would see "infinite blueshift" and the entire history of the universe in the region _beyond the event horizon_ of a rotating black hole. However, it is very likely that such solutions are not stable solutions.
  8. Dec 20, 2004 #7
    There is a recent proposal by:http://arxiv.org/abs/astro-ph/0412503

    on a test that I made statement to, on the superstringtheory forum 3 yrs ago.

    The above (link) academic proposal uses an almost identical test as to what I suggested. I have taken my test a little further these days, and the above author fails to include allowances for the'Quantum Efficency Wave' , the amplitude of which I have calculated and theoretically investigated.
  9. Dec 21, 2004 #8


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    Is this "Quantum Efficiecy Wave" an invention of yours? I went through six years of QM, and such thing was never mentioned.
  10. Dec 21, 2004 #9


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    On the other hand... What would you see if you had a black hole forming in front of you? As the material collapsed onto and beyond its event horizon would it not be red shifted and time dilated and be frozen at the event horizon? If so how come we see black holes at all - if indeed we do?

    Just a thought

  11. Dec 21, 2004 #10

    Not peer or Archived..its within Superstringtheory forum boards.

    I proposed that there was a definate cause to investigate sending correlated photons/atoms, close to a Table top Blackhole(T-B-H was proposed by Ulf Leonhart?), with informatzion being relayed from inside/below the event horizon.

    This was independant and avante guarde, but nevertheless, my Idea.

    P.S I do believe that Penrose fed Hawking the Idea on how to extract informatzione from a Blackhole, in the sixties?..this no doubt lay dormant in my mind for some practical length of time!

    Here is a good paper that the authors details some aspects of interest:http://www.optica.tn.tudelft.nl/publications/docs/2_25_2004_12_29_02prl02933.pdf
    Last edited: Dec 21, 2004
  12. Dec 21, 2004 #11

    Chroot has singled me out again as a crackpot theorist:If you think walking backwards into a black hole is more realistic than what my response is?..then I would gratefully plead you to ban me for good?..if you fell agrivated by my obvious more varied knowledge than your truly, then please go ahead.

    The above was my reply to him
  13. Dec 21, 2004 #12
    I alos printed out a copy before my ban takes effect ;)
  14. Dec 22, 2004 #13
    "If an external observer sees me slow down asymptotically as I fall, it might seem reasonable that I'd see the universe speed up asymptotically-- that I'd see the universe end in a spectacular flash as I went through the horizon. This isn't the case, though. What an external observer sees depends on what light does after I emit it. What I see, however, depends on what light does before it gets to me. And there's no way that light from future events far away can get to me. Faraway events in the arbitrarily distant future never end up on my "past light-cone," the surface made of light rays that get to me at a given time." ~ the first link in message #6

    This is a good answer against what I was originally asking about. Just thought I'd write it here for anyone who didn't want to read the whole page. It still may be possible to "see" the universe end while falling into a wormhole from this explanation just below from the same link:
    "That, at least, is the story for an uncharged, nonrotating black hole. For charged or rotating holes, the story is different. Such holes can contain, in the idealized solutions, 'timelike wormholes' which serve as gateways to otherwise disconnected regions-- effectively, different universes. Instead of hitting the singularity, I can go through the wormhole. But at the entrance to the wormhole, which acts as a kind of inner event horizon, an infinite speed-up effect actually does occur. If I fall into the wormhole I see the entire history of the universe outside play itself out to the end. Even worse, as the picture speeds up the light gets blueshifted and more energetic, so that as I pass into the wormhole an 'infinite blueshift' happens which fries me with hard radiation. There is apparently good reason to believe that the infinite blueshift would imperil the wormhole itself, replacing it with a singularity no less pernicious than the one I've managed to miss. In any case it would render wormhole travel an undertaking of questionable practicality."

    I still think it's an interesting thought experiment to imagine a universe that never ends, never repeats, and doesn't approach something to infinity (such as if the universe exponentially expands forever). This would still be possible if space, matter, and time are quantised because eventually every possiblity would be played out, but could be played out in a neverending amount of different orders.
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