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Dark matter/Dark energy

  1. Apr 16, 2013 #1
    Is there a possibility that dark energy comes from mass that travels faster than the speed of light, making its mass imaginary?
  2. jcsd
  3. Apr 16, 2013 #2


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    hi tmv3v! welcome to pf! :smile:

    e = mc² (and the c² is nothing more than a conversion factor),

    so if the mass was imaginary, wouldn't the energy be imaginary also? :wink:
  4. Apr 16, 2013 #3
    couple of other points nothing moves faster than the speed of light and particles with mass cannot reach light speed. Dark energy is a mysterious energy that is attributed to causing expansion. No one knows where it comes from IE its source. However it is often attributed to being the energy driving expansion.

    Dark matter has nothing to do with dark energy by the way, also its slower than relativistic speeds

    there are numerous articles in the FAQ subforum that would be handy for you

    Ned Wrights FAQ has some useful information you may want to check out

    also http://www.astro.ucla.edu/~wright/cosmology_faq.html

    myself and other PF members wrote the article contained in this thread its lengthy as it covers expansion principles, redshift and cosmic distance ladder in one overall article. However you will find some info on dark energy in its contents as well.


    the article is easily found here.

    Welcome to the forum
    Last edited: Apr 16, 2013
  5. Apr 16, 2013 #4
    Thanks you the reply:) I was thinking thats why its hard to detect as they are travel so fast.

    Thanks for the reply:). Is there a prove that nothing can travel faster than the speed of light? Is there a possibility that if we input sufficient energy we can somehow exceed it and go up a dimension to remain faster than the speed of light?
  6. Apr 16, 2013 #5
    This wiki article describes some of the tests done. There have been extensive testing of GR and SR. For that matter extensive tests on pretty much all of Einsteins theories. None of his theories have been found wrong.


    the above section also covers why a mass particle cannot reach the speed of light.
  7. Feb 19, 2014 #6
    This is not entirely true. Einstein's full equation is E=mc2/√(1-v2/c2). Meaning if the mass were imaginary it could travel a speeds greater than c in order to produce a real (meaning non-imaginary) energy. This particle you're referring to is known as a tachyon and is plausible theoretically but there is no evidence of it's existence. These types of particles could theoretically be as varying as the particles we know in the real world and be the cause of the accelerated expansion of the universe (dark energy). However, dark matter is certainly some type of particle that behaves as having a real and positive mass.
  8. Feb 9, 2016 #7
    Informative post - For my two cents if others have been needing a a form , my husband edited a blank version here http://goo.gl/EJLYur
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