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Simulated Universe

Posted by Zonk on from the not-the-matrix dept.

anonymous lion writes "A story in the Guardian Unlimited reports on The Millennium Simulation saying that it is 'the biggest exercise of its kind'. It required 25 million megabytes of memory to take our universe's initial conditions along with the known laws of physics to create this simulated universe." From the article: "The simulated universe represents a cube of creation with sides that measure 2bn light years. It is home to 20m galaxies, large and small. It has been designed to answer questions about the past, but it offers the tantalising opportunity to fast-forward in time to the slow death of the galaxies, billions of years from now."

8 of 332 comments (clear)

  1. SECRET CHEAT by rebug · · Score: 5, Funny

    Just type "FUND" a few hundred times.

    Do it before you build anything, because it causes earthquakes.

    --

    there's more than one way to do me.
  2. Re:25 TB? That's nothing. by Seumas · · Score: 5, Informative

    I'm pretty sure that they're talking about RAM. And yes, 23 terrabytes of RAM is a ton.

  3. Google Maps by msbmsb · · Score: 4, Funny

    So when will Google Maps be available for this universe?

  4. Dudes... by GeorgeMcBay · · Score: 5, Funny

    What if we're in a simulated universe, simulating other universes?

    Whoaaa.

    Pass the bong, dude.

  5. Predicting the future by XXIstCenturyBoy · · Score: 5, Interesting

    I always though that a computer large enough to handle a simulation of the universe would allow us to predict the future, even at individual level if the simulation was advanced enough.

    And then I realized that the smallest simulation of the universe would probably be the size of the universe.

    It got very confusing at that point.

  6. Re:I thought by Anonymous Coward · · Score: 5, Informative

    They have stuff like stars that are older than some estimates of the universe's age

    No, they don't. This has happened a few times in the past, e.g., when they didn't know about the different populations of stars, but currently there isn't an age problem.

    and missing matter in the form of dark matter that they can't account for

    We don't know what dark matter is, but we know enough about its gravitational properties -- that's why it was postulated to exist, after all -- to simulate its effects on these scales.

    How are they supposed to simulate the universe, if the model they have is so badly flawed.

    The models we have are not as badly flawed as you think they are. But even if they are flawed, that's the point of the simulation: to test the validity of the model. If the simulation's results don't agree with observations, then that tells us about where the model fails.
  7. Re:25 TB? That's nothing. by andyh1978 · · Score: 4, Informative
    I figured they meant 25 TB of RAM. Which would be much more impressive.
    This was on Newsnight a couple of days ago; the researcher said their machine had 1TB of RAM.

    That's confirmed in page 18 of their paper: http://arxiv.org/PS_cache/astro-ph/pdf/0504/050409 7.pdf
    The calculation was performed on 512 processors of an IBM p690 parallel computer at the Computing Centre of the Max-Planck Society in Garching, Germany. It utilised almost all the 1 TB of physically distributed memory available. It required about 350000 processor hours of CPU time, or 28 days of wall-clock time.
    The mean sustained floating point performance (as measured by hardware counters) was about 0.2 TFlops, so the total number of floating point operations carried out was of order 5x10^17.
  8. IBM was doing this in the '70s... by argent · · Score: 4, Funny

    At least this was going around when I was at Berkeley:

    NEW OPERATING SYSTEM:

    Because so many users have asked for an operating system of even greater capability than VM, IBM announces the Virtual Universe Operating System --- OS/VU.

    Running under VU the individual user appears to have not merely a machine of his own, but an entire universe of his own, in which he can set up and take down his own programs, data sets, system networks, personnel and planetary systems. He need only specify the universe he desires, and the OS/VU system generation program (IEHGOD) does the rest. This program resides in SYS1.GODLIB. The minimum time for this function is 6 days of activity and 1 day of review. In conjunction with OS/VU, all system utilities reside in SYS1.MESSIAH. This program has no parms or control cards, as it knows what you want to do when you execute it.

    Naturally, the user must have attained a certain degree of sophistication in the data processing field if an efficient utilization of OS/VU is to be achieved. Frequent calls to non-resident galaxies can, for instance, lead to unexpected delays in the execution of a job. Although IBM, through its wholly-owned subsidiary, the United States, is working on a program to upgrade the speed of light and thus reduce the overhead of extraterrestrial and metadimensional paging, users must be careful for the present to stay within the laws of physics. IBM must charge an additional fee for violations.

    OS/VU will run on any IBM x0xx equipped with the Extended WARP Feature. Rental is 20 million dollars per cpu/nanosecond.

    Users should be aware that IBM plans to migrate all existing systems and hardware to OS/VU as soon as our engineers effect one output that is (conceptually) error free. This will give us a base to develop an even more powerful OS, target date 2001, designated as 'Virtual Reality'. OS/VR is planned to allow the user to migrate to totally unreal universes. To aid the user in identifying the difference between 'Virtual Reality' and 'Real Reality', a file containing a linear record of multisensory total records of successive moments of now will be established. It's name will be SYS1.EST.