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Impedance mismatch at the universes edge

  1. Nov 17, 2008 #1
    Hey all

    As is my way I pondered what would happen to light (and other emr) when it reaches the edge of the universe.

    First one must assume the universe has an edge.

    Anyways I figured there is possibly two cases
    1./ The universe is expanding at the speed of light so nothing ever reaches the edge
    2./ As light reaches the border between the known and the unknown it must encounter an impedance mismatch.

    Working on 2, I would assume the edge of the universe would be a perfect mismatch, in that everything that reaches it reflects back. Would that make it a perfect mirror?

    Given that one must think then that perhaps some of the cosmological features we see in the universe are in fact reflections.

    If the reflection is not perfect but in fact diffused, then perhaps that would fill the universe with a even glow of electromagnetic radiation in much the same way as white walls help fill a room with light, even the dark corners where the bulb is eclipsed by a chair.

    Hmm CMB?

  2. jcsd
  3. Nov 18, 2008 #2


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    Staff: Mentor

    The universe has no edge. Please read the sticky'd thread at the top of this forum to learn about how the universe can be finite, yet not have an edge.
  4. Nov 18, 2008 #3
    I read the sticky.

    And I said one must assume the universe has an edge. it is a prerequisite for my mind experiment.

    No one here can make such a bold statement as the Universe has no edge or no center.

    Quote "the Universe in fact contains neither a centre or an edge"

    I find it incredulous that thinking people can use the word FACT to replace the word THEORY. Until its proven beyond a shadow of a doubt its theory nothing more.

    I am religious therefore its a FACT god exists
    I am atheist therefore its a FACT god doesn't exist
    I am a child therefore its a FACT Santa exists
    I am a student therefore its a FACT anything my teacher says is true.
    I am a teacher therefore it is a FACT anything I say is true, and DON'T EVER QUESTION ME

    Isn't anyone here taught to think for themselves?

    One thread on the subject...

    WALLACE "On to the question, the Universe, at least according to current theory, has no centre." (or edge )

    Notice the little bit about "current theory" which means IS NOT A FACT!

    Given that theories are derived from ideas that fit the current known state of things at least until something better comes along. someone who calls himself a PF MENTOR should perhaps be a little less closeted in his idea's

    Why do people insist on repeating the errors of history.

    One last thing....
    While I respect the "everyone on the same page" idea (to keep the loons out, er me I suppose), Isn't that a fool hardy approach to a discussion. It is saying lets set the facts before we discuss anything. But if you set the FACTS to the wrong set of theories then all discussion on the subject is wrong! starting from an invalid point makes everything derived from it invalid.
    Though of course it does give people a nice cosy feeling of safety inside their belief system

    Last edited: Nov 18, 2008
  5. Nov 18, 2008 #4


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    Staff: Mentor

    Starting with that assumption instantly leads to predicted observations about the universe that contradict what is actually seen. You'll find ample discussion of that in that thread and others (and, it would appear you already have, yet you have chosen to completely ignore what you've read). There is no point to rehashing the same discussion again here.
    Unwillingness to accept that people have already throught through the concept you are discussing meeans the one operating on "belief" here is you.

    Either way, there is no purpose for this thread. If the thread I referenced isn't enough, you can search the forums for the dozens of similar threads where the idea is discussed and read them as well.

    [edit] Please note also that we have a rule against unverified personal theories. The type of speculation you are doing is not acceptable discussion here.

    Thread locked.
    Last edited: Nov 18, 2008
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