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No Naked Black Holes

Science News reports on a paper to be published in Physical Review Letters in which an international team of researchers describes their computer simulation of the most violent collision imaginable: two black holes colliding head-on at nearly light-speed. Even in this extreme scenario, Roger Penrose's weak cosmic censorship hypothesis seems to hold — the resulting black hole (after the gravitational waves have died down) retains its event horizon. "Mathematically, 'naked' singularities, or those without event horizons, can exist, but physicists wouldn't know what to make of them. All known mechanisms for the formation of singularities also create an event horizon, and Penrose conjectured that there must be some physical principle — a 'cosmic censor' — that forbids singularity nakedness ..."

13 of 317 comments (clear)

  1. Does anyone else get sad? by bonch · · Score: 4, Insightful

    Does anyone else get sad at the thought that there are so many weird things in the universe you may not learn the answers to in your lifetime? What if everyone posting here never finds out the reason for the cosmic censor? Sort of depressing.

    1. Re:Does anyone else get sad? by fortunato · · Score: 5, Insightful

      Does anyone else get sad at the thought that there are so many weird things in the universe you may not learn the answers to in your lifetime?

      I would submit that this is the lament of every intelligent being since the dawn of time (assuming there is a dawn of time).

    2. Re:Does anyone else get sad? by mcgrew · · Score: 4, Insightful

      Not the least. If I knew everything, I would no longer have the joy of learning.

    3. Re:Does anyone else get sad? by mcgrew · · Score: 3, Insightful

      One of my college instructors (Dennis Ringering, SIU, probably retired by now) was fond of telling students who thought they knew everything "I've forgotten more than you ever learned."

    4. Re:Does anyone else get sad? by Fumus · · Score: 3, Insightful

      Ecc 1:18
      For in much wisdom [is] much grief: and he that increaseth knowledge increaseth sorrow.

  2. There is no singularity by Flentil · · Score: 3, Insightful

    If photonst have weight, they can be effected by gravity, and a black hole can form around any object with sufficient mass to trap light. That's all there is to it. There is no magical singularity where the laws of physics break down. There doesn't need to be.

    1. Re:There is no singularity by nusuth · · Score: 3, Insightful

      I get your point but I don't agree. You could build a simulation model by using any physics we might care to simulate, and ask a question to the model. The answer may be what you expect or it may be something unexpected. The former case is not terribly useful, it just says your assumptions about the universe is consistent with your expectations about the universe. That is nice to know. In the latter case, the physics of the model or your expectation is wrong. You wouldn't know which by just looking at the model, but knowing that at least one of them is wrong is *very* valuable information. So the experiment is worth doing.

      --

      Gentlemen, you can't fight in here, this is the War Room!

  3. Re:Penrose is smart by DirtySouthAfrican · · Score: 4, Insightful

    Heh... I knew who Roger Penrose was long before I heard of Richard Dawkins, and I suspect that I'll forget who Richard Dawkins soon enough. But I'm biased for being a physicist.

  4. Re:Cosmic Censor by Anonymous Coward · · Score: 1, Insightful

    Sure is - black holes have mass and are therefore Catholic.

    For some reason your reference reminds me of Hotel California.

    Mirrors on the ceiling,
    The pink champagne on ice
    And she said we are all just prisoners here, of our own device
    And in the master's chambers,
    They gathered for the feast
    The stab it with their steely knives,
    But they just can't kill the beast

    Last thing I remember, I was
    Running for the door
    I had to find the passage back
    To the place I was before
    relax, said the night man,
    We are programmed to receive.
    You can checkout any time you like,
    But you can never leave!

    The bolded portion bears the strongest relationship to black holes, but possible Christianity references abound. Maybe scientists should name some of them: Hotel California, purgatory, hell and call the one that gets us "the beast".

  5. Computer simulation, eh. by 75th+Trombone · · Score: 1, Insightful

    I can't get over this sort of story. "We programmed our INCOMPLETE understanding of the cosmos into this simulation, which tells us X, therefore X is more likely."

    Anything based on a computer simulation is based on our arbitrarily incomplete knowledge. To base even the least significant conclusions upon it seems laughably irresponsible and unscientific.

    But hey, I was a music major, so what do I know.

    --
    The United States of America: We do what we must because we can.
    1. Re:Computer simulation, eh. by Ihlosi · · Score: 4, Insightful

      Anything based on a computer simulation is based on our arbitrarily incomplete knowledge. To base even the least significant conclusions upon it seems laughably irresponsible and unscientific.

      We eagerly await your analytical solution to the n-body-problem. I mean, it's really simple stuff, right?

      Until you're finished, we'll have to calculate all those spacecraft trajectories with computer simulations.

  6. Re:Discrete; you know what this means? by 4D6963 · · Score: 3, Insightful

    -1, Unfalsifiable

    Dare I elaborate, if you wanted to make up a generic unfalsifiable claim on purpose that's probably what you would come up with.

    --
    You just got troll'd!
  7. Re:Move Violent?... by Loibisch · · Score: 2, Insightful

    You probably need to get yourself an extra few dimensions to make 3 particles collide exactly head-on.