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The What is? Post

  1. Nov 8, 2012 #1
    The "What is?" Post

    I'm almost deathly afraid of posting here from the responses I got on IRC.

    Just starting out in theoretical physics and finding my way around manually, having done some light research, and having studied group and set theory extensively enough, I'm wondering a few things.

    1. What -is- energy in the universe? What is it comprised of?
    2. Is "Dark Energy" or "Dark Matter" some unit of space?
    3. Why can electromagnetic waves travel through a vaccum? Isn't there some sort of medium they need to go through? Wouldn't Dark Energy explain that medium by being the "energy" of space that particles propagate through?
    4. Space and Time. What if they were energies? What if Spatial Energy, as I'd like to call it, is something that is constantly additive relative to what it affects? What if Temporal Energy was constantly subtractive? (Think of it like this: in a universe with only Spatial Energy, as I move, I would see every "frame" of my movement as I walked along, and in Temporal Energy, I wouldn't be seeing anything, because it'd be constantly subtracting my mass from the universe.)
    5. What is a field? Is it comprised of particles, waves, what?

    I hope that I don't get run out with this. I'm not an expert, and I'm just startiing, so please don't rip me apart too harshly. Thanks in advance. :)
  2. jcsd
  3. Nov 8, 2012 #2


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    Re: The "What is?" Post

    I suggest you Google (or Bing) these items - read Wikipeida articles.
  4. Nov 8, 2012 #3


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    Re: The "What is?" Post

    There is far too much for just one thread. As Mathman says, read up on each topic separately. When you have a single (closed) question about a single topic, submit it here and you may get some useful answers.
    PF is not a potted Physics Course.
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