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Dark Energy- Information

  1. Apr 2, 2008 #1
    Hello everyone! I am writing a paper for a final in a basic Cosmology course in college. I chose my topic to be Dark Energy. I am wondering, does anyone here have any good links or sources that I may consult and reference in writing my paper? There is no specific aspect I am focusing on, just general information about Dark Energy, what it is/how it affects us etc.

    I'm just looking for information, the more reading, the better! (But not any papers that are too technical please, calculus isn't even a requisite for this course)

    Thanks a bunch, Jared
  2. jcsd
  3. Apr 2, 2008 #2
    This can go so many directions I can't count. How much depth to you wish to get into? Do you want to get into the role it plays in cosmology or just stick with the different ways it is theoretically defined?

    The original form Dark Energy took was the cosmological constant. Which later was called a mistake, then resurrected in cosmology. It takes many different forms in many theories. In fact a search of http://arxiv.org/ for "dark energy" exceeds the hit limit for returnable results.

    Perhaps searching http://arxiv.org/ and narrowing your question would make it easier to respond.
  4. Apr 2, 2008 #3


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    Try http://supernova.lbl.gov/~evlinder/sci.html" [Broken] page for starters.
    Last edited by a moderator: May 3, 2017
  5. Apr 3, 2008 #4
    Very nice. I'll have to browse through that myself.
    Last edited by a moderator: May 3, 2017
  6. Apr 3, 2008 #5
    Okay, so I decided this may help. This is my topic sentence, and basically what the paper is going to be covering.

    "Dark energy is a term given to hypothetical, homogeneous energy that is everywhere in the universe and is an opposing force to gravity; it is widely believed that dark energy provides for the continuous expansion of the universe."

    I'm going to talk about what it is, and it's function primarily. Thanks for the links so far. :)
  7. Apr 3, 2008 #6


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    Good so far but

    energy is not force, these are different physical quantities, so that statement isn't quite right. It would be like equating an acceleration with a velocity. The important thing about DE is that it has negative pressure. Through the Friedmann equations, which are a solution the the Einstein Field Equations (basically the mathematical description of GR) it is observed a source of energy with sufficiently negative energy will cause the expansion of the Universe to accelerate, which is the key point. But dark energy itself is not a force, it is an energy source.

    Again, be careful with the words you use. Dark Energy is not needed in order for the Universe to continually expand. The key point about DE is it makes the expansion accelerate, but expansion itself is a consequence of the Big Bang and does not require the existence of dark energy.

    Let me know if any of the above was confusing!
  8. Apr 4, 2008 #7
    Can anyone see a similarity between the above statement and what used to be referred to as the 'aether'?

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