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Scientists Complete Universe Millennium Simulation

Posted by timothy on from the prayer-wheels-can-stop dept.

james tech writes "The Virgo Consortium recently completed its massive "Millennium Simulation", tracing the universe's evolution from its early origins to present day. To simplify the computations, they considered only dark matter which composes most of the universe. Using a 512-node cluster with IBM processors, the group produced over 20 terabytes of data with some of the most breathtaking images of the universe never seen. A visible matter simulation is underway, at a lower resolution."

2 of 375 comments (clear)

  1. evidence by resistfascism · · Score: 5, Interesting

    Besides the argument that stars orbiting around the fringes of galaxies appear to be moving too fast to stay in orbit without extra mass, what other observable evidence of dark matter is there?

    1. Re:evidence by gr8_phk · · Score: 3, Interesting
      "Besides the argument that stars orbiting around the fringes of galaxies appear to be moving too fast to stay in orbit without extra mass, what other observable evidence of dark matter is there?"

      I looked into that whole thing. Most of the people who make that claim refer to Keplers laws of motion for orbiting bodies. If you assume the stars orbit a heavy core and don't interact with each other you get a galactic rotation curve that tapers off with radius. Real measured curves are nearly flat, so they conclude some "dark matter" that has some really unintuitive properties (see below). My own calculations of a rotation curve for a uniform flat disk of stars using interactions between all stars shows velocity increasing roughly linearly all the way out, and increasing even faster toward the edge. I don't think we should be suprised that observation lies somewhere between these two models. My distribution of stars is not accurate.

      Stupid properties of dark matter: The interaction with regular matter must be asymetric. Why? Because they model it as a sphere of dark matter enclosing a disk shaped galaxy to get the expected rotation curve. If dark matter interacted with itself and visible matter in the same way visible matter interacts with itself, they should have the same distribution. I think they just observed that a big sphere of stuff would make their flawed model match reality and said "oh there must be this goofy thing here". Remember, there are NO direct observations of dark matter (or energy).

      The tragedy of Einstein is that he convinced physicists that strange nonintuitive things are a part of the universe. This encourages the promotion of nifty off-the-wall sounding theories that make headlines to get funding.

      I've said it here before: The only dark matter is between the astrophisicists ears.