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

Dark Matter ?

  1. Feb 9, 2008 #1
    I keep hearing about how this exotic Dark Matter is supposed to be evenly spread out across the universe... and that it doesn't interact with normal matter, only through gravitation, etc...

    My question is, how is this the valid conclusion from the fact that our Gravitation formulas don't seem to work properly? Why do physicists make up particles instead of just considering the possibility that our formulas for gravitation outside our solar system may be wrong, or something like that? I mean... making up a whole new particle and claiming that it fills all space around us seems like the hard way to make the math come out.
  2. jcsd
  3. Feb 9, 2008 #2


    User Avatar
    Science Advisor

    There is a theory (called MOND) which does exactly what you are suggesting (changing formulas for gravity). The problem with MOND seems to getting it to be consistent withh all observations about galactic motion, etc.
  4. Feb 9, 2008 #3


    User Avatar
    Staff Emeritus
    Science Advisor

    I think you may be slightly confused between dark matter and dark energy. Dark Energy is the stuff that is proposed to be everywhere around us, spread out evenly, which is causing the acceleration of the expansion of the universe. Dark matter is allowed to clump, like normal matter.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook