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Dark energy

  1. Jun 15, 2014 #1
    Ok this may be another stupid Question that I always seem to ask! Does Dark Energy follow the same rule as energy? E=MC^2 or E=MC2?
  2. jcsd
  3. Jun 15, 2014 #2
    we don't know what dark energy is exactly, so we have no idea what particle to use in that formula.
  4. Jun 15, 2014 #3
    Thanks for your answer
  5. Jun 16, 2014 #4


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    The name "dark energy" is perhaps a poorly chosen one. We are as yet completely clueless to the underlying mechanism behind it. The simplest model which explains dark energy is the regular cosmological constant. In this case, the dark energy is a manifestation of a constant of integration in Einstein's Field Equations. As such, it does not behave like any particles that we know of.
  6. Jun 16, 2014 #5
    Thanks so much for your answer! Dark energy is a mysterious thing. From what I've read it seems to be growing stronger too.
  7. Jun 16, 2014 #6
    I just wanted to clarify I meant to say seems to to growing stronger but not growing in the total percentage of it to everything else in the universe
  8. Jun 16, 2014 #7


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    No, it is not. As far as is known, dark energy has been around since the beginning or the universe (or shortly thereafter) and has always had the same energy density per unit volumn. What you are probably getting confused by is the fact that the EFFECT is getting larger because the space between galaxies is getting larger. It's a snowball effect.
  9. Jun 16, 2014 #8
    Does dark energy actually exist or is it a theory? Any proof/evidence of it?
  10. Jun 16, 2014 #9


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    I think you have a fundamental misunderstanding. Experimental evidence is unequivocal that SOMETHING is causing the universe's expansion to accelerate. We have no idea WHAT is causing it so someone made up the name "dark energy" as a stand-in phrase so that we don't have to go around all the time saying "whatever it is that is causing the universe's expansion to accelerate"
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