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Expanding universe?

  1. Sep 20, 2009 #1
    When people say the universe is expanding, do they mean that the galaxies etc are moving farther apart from each other (i wonder how fast o_O)? or does that mean that more matter is being produced somewhere in the universe, causing it to expand...
  2. jcsd
  3. Sep 20, 2009 #2


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    Staff: Mentor

    Galaxies are moving apart and that means there's more space. No new matter, though.
  4. Sep 20, 2009 #3
    Not only the universe is expanding, it is actually accelerating. It's like throwing a baseball and it moves faster and faster rather than gradually slows down.
  5. Sep 21, 2009 #4
    then what? after it is done accelerating it compacts again and "the big bang" happens again? if so, i wonder how many times this has happened? Has this happened an infinite number of times? will history repeat itself? Has the earth been here before the big bang? What's the point to life if we cannot possibly last past the big bang? Maybe some life forms have survived a big bang? gone past the universe assuming there are no boundary's, which i doubt there are. Are there more than one universe? There are planets, solar systems, galaxies, and universes? Maybe something beyond universes? Most of the questions will probably never be answered by humans, but maybe they will? We would have to leave earth someday in order to answer these questions, and survive other obstacles we don't have to worry about for now, gamma ray bursts, black holes, the works. How can we possibly leave the earth as a human race if we cannot come together in harmony with other people on this earth? In order to answer and achieve this, people need to start thinking for the greater good, not for themselves. This has caused corruption in governments and company's as we all know, limiting our abilitys as humans.

    anyone care to continue my rant or encourage another?
  6. Sep 28, 2009 #5
    The universe is going to keep accelerating so another big bang isn't likely under this theory. Actually, quite the opposite might happen, the big...freeze? With so much space, all matter will spread out due to the natural entropy of the universe. Billions of years later there will only be black holes and they will eventually die off leaving all the matter in the universe too spread out making it impossible for life. Its hard to imagine but before the big bang, there was nothing. Period. So technically the big band created the universe in a sense.
  7. Oct 3, 2009 #6
    Interesting. I remember i saw a documentary of discovery science 2 years ago where a scientist mentioned something about an invisible layer (some sort of a shield) at the end of the universe. I am pretty sure i heard that right. If so, then what is the meaning of that shield? Could it be limit of expansion or....
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