Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Why just Dark Matter ?

  1. Jun 21, 2003 #1

    drag

    User Avatar
    Science Advisor

    Greetings !

    I wonder if we really need to pursue just the dark matter
    direction to explain why galaxies turn the way they do and
    the whole cosmology part about the form of Universal space-time.

    Has there been an attempt to explain the motion
    of galaxies by adding another Universal law or purhaps
    altering the law of Gravity for larger scales (in a way
    partially similar to what Einstein attempted to justify
    a supposedly stable Universe) ? If so (talking about an
    extension of Gravity), has there been a consistent pattern
    observed - a similar connection between the normal mass of
    the galaxy and the estimated required mass of the dark matter ?

    In addition, could such an assumption experience difficulties
    or alternativly help solve some other cosmological puzzles ?

    Thanks ! :smile:

    Live long and prosper.
     
    Last edited: Jun 21, 2003
  2. jcsd
  3. Jun 21, 2003 #2

    Labguy

    User Avatar
    Science Advisor

  4. Jun 21, 2003 #3

    mathman

    User Avatar
    Science Advisor
    Gold Member

    There is an alternate approach called MOND (modified Newtonian dynamics) proposed by Milgrom along the lines you suggest. It was written up in a recent issue of Scientific American. The major problem with the approach is that it is rather ad hoc, and difficult to test. I don't know if Milgrom and people working on that idea have come up with some test to distinguish it from non-baryonic matter. Some dark matter is baryonic, but most of it is not.
     
  5. Jun 22, 2003 #4

    drag

    User Avatar
    Science Advisor

    Greetings !

    I just read a short stroy in a paper today mentioning
    Milgrom and the two different approaches to the problem.
    Is seems that recent surveys and observation of the dynamics
    of settelite galaxies (smaller galaxies orbiting larger
    galaxies) are supportive of the Dark Matter hypothesys and
    do not favour the alteration of the law of Gravity possibility.

    However, the short story that I read did not mention any more
    specifics or technical info, so I'd appreciate relevant input.

    Thanks ! :smile:

    Live long and prosper.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Why just Dark Matter ?
Loading...