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NASA Scientists Simulate Black Hole Collision

Posted by ryuzaki0 on from the big-bangs-and-other-fun-videos dept.

Krishna Dagli writes to tell us Yahoo! News is reporting that NASA scientists have managed to simulate the merger of two massive orbiting black holes. Using technology from Silicon Graphics, Inc. built from 20 SGI Altix systems the team was able to show how the resulting gravitational waves would interact with surrounding space.

14 of 63 comments (clear)

  1. didn't know processors have memory by uioreanu · · Score: 3, Funny
    By linking four, 512-processor Altix systems .... NASA enabled the scientists to access all of the processors' memory at once.
    --
    cut this signatures madness. stop reading them now!
    1. Re:didn't know processors have memory by eliot1785 · · Score: 3, Informative

      They actually have several layers of memory (registers, L1, L2...), it's just not called that.

      I don't think that's what they meant though.

    2. Re:didn't know processors have memory by Anonymous Coward · · Score: 2, Informative

      What they mean is that they were able to join the address spaces of the different machines to form a single, unified one. Without any extra software, a processor can thus execute load and stores to the memory of a different machine simply by using an address that is mapped to the memory of another SGI Altix - the machine does all the rest.

      In other words, you're able to use shared-memory forms of multi-processor programming, such as threads, instead of message-passing, as is used e.g. by clusters (think pthreads instead of MPI).

    3. Re:didn't know processors have memory by prefect42 · · Score: 3, Informative

      I think you need to relax your terminology a little. On an Altix box you have what used to be called C-Bricks. Basically a unit that contains processors and RAM. Those all link together over NUMAFlex (with appropriate routers) to form your large shared memory machine. But the RAM is still localised (as it's a NUMA architecture). So 'main memory' should be considered as 'owned' by a processor (or processors). If you'd made an OpenMOSIX cluster to match you'd refer to it as a machine's memory, but since all these C-Bricks form a single machine whole, you can't do that.

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      jh

  2. imagine by Criliric · · Score: 2, Funny

    imagine a beowolf.... nevermind :)

  3. Black holes colliding? by MindCheese · · Score: 4, Funny

    Man, that would suck.

    1. Re:Black holes colliding? by MickDownUnder · · Score: 3, Funny

      I think you meant.... that would be heavy man !

  4. Summary by miikrr · · Score: 2, Interesting

    The first video is looks pointless. It just shows two black holes circling around each other doing nothing, and then the clip just ends. Einstein's clip shows two black holes merging into one big-ass black hole, which shows a much more interesting theory than "nothing really happens when two black holes meet, but here's a video anyway!"

  5. How? by squoozer · · Score: 3, Insightful

    I wasn't aware that we understood how one black hole worked so how can this team perform a simulation of two coming together and hope to get anything useful out? I admit there is an outside chance they will stumble on the correct result but can they prove it's correct?

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    I used to have a better sig but it broke.
    1. Re:How? by amRadioHed · · Score: 2, Informative

      The thing we don't understand about black holes is the singularity itself. The observable behavior of the black hole is mostly understood and I think that is what is being simulated. The stuff that is truly mysterious is hidden away within the event horizon.

      --
      We hope your rules and wisdom choke you / Now we are one in everlasting peace
  6. Dude ... by Savage-Rabbit · · Score: 4, Funny
    Man, that would suck
    ... don't be so dramatic, intellectual and moral black holes collide on Capitol Hill every day and we still haven't been sucked in.
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    Only to idiots, are orders laws.
    -- Henning von Tresckow
  7. Re:Dup? by DoctorBit · · Score: 2, Informative

    Yep, http://science.slashdot.org/article.pl?sid=06/04/1 9/1443210

  8. Some more info. by Stoutlimb · · Score: 4, Informative

    I actually went to a seminar years back by one of the individuals working on this. The equation alone filled pages, and was something he had to derive by hand. He showed us a cgi video of the results. The 2 black holes approached, snapped together, and the resulting larger black hole temporarily oscillated. The strange part was partway through the oscillation, the black hole just popped out of existence, and then reappeard several seconds later.

    In the question and answer period, a student asked why this gap in the calculations. The professor explained there was no gap in the calculations, but rather, the result of the calculations was non-euclidean in nature, so it was physically impossible to display it in a 3d model. At about that time, half of the undergrad audience whispered a Keanu Reeves style "whoah..."

    Don't ask me any of the details, this was years ago in a course on stellar astrophysics that I have mostly forgot. This is just something anecdotal. Astrophysicists have been working on this black hole merger thing for a very long time. The computer labs at the time had P133's running. I'd love to see what they're doing now, but that site wasn't very big on actual information.

  9. Addendum by Stoutlimb · · Score: 2

    I went through the videos on that site I missed. I could swear I saw the EXACT SAME videos at the 1993 conference. Especially the one that showed the gravity waves of the two merging black holes. I swear I even see the resulting black hole wink out for a frame or two. They really don't show the actual merger in very much detail at all, I think this is on purpose. I think that's why they havn't posted anything that clearly shows the merger, because I very much doubt an observer at the merger of 2 black holes would just see it wink out of existence like that. (Not that an observer would survive that kind of event, but that's neither here nor there.) For public release I guess it's bad to admit they don't have all the answers yet.