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Mass Question

  1. Mar 7, 2007 #1
    Random question, but is it true that all information, like brain neurons (ideas), light, radio waves, etc... has a mass?

    Basically if anything moves then it transfers energy and must have a mass. So the Universe is ALL mass?

    Also, what would "space" be defined as in terms of mass.
  2. jcsd
  3. Mar 7, 2007 #2
    Photons have no mass, they have energy. Light and radio waves are photons. Just because something moves, does not mean it transfers energy. Think of a a Cosmic ray travelling through a vaccum, there is nothing to transfer its energy to.

    As for space, a more appropriate term would be energy density.

    I like how you are thinking about such topics and I appreciate your creativity.
  4. Mar 7, 2007 #3
    So what are photons and cosmic rays made up of?

    Also if light gets affected by gravity, it must have a mass.
    Doesn't light travel for millions of miles then starts to bend because of gravity?

  5. Mar 7, 2007 #4
    I personally don't have much information on this topic but here is what I know;

    Photons do have a Relativistic Mass when travelling with a speed greater than zero.

    But when it comes to waves, they don't need a mass to be effected by the gravity, According to General Relativity of Einstein gravity is curvature in space time which means a geometrical phenomena. As it doesn't involves force, the wave won't need to have a mass.

    For the best answers try writing this question in Relativity forum.
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