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Question about space-time

  1. Dec 30, 2009 #1
    Hello. This is my first post on the forum. Without a long introduction I'm just an average guy with a huge amount of curiosity but know nothing. I have a couple questions (very theoretical I'll warn you)

    Space and time is interweaved, like a fabric (thus spacetime). You move through it, gravity affects it (or rather gravity is the affect of mass bending spacetime). Could it be possible that, in theory, you can travel through one of the woven fabrics given the technology and better understanding (picture a knitted blanket 2 different colors, space is blue, time is purple)?

    The other question is, if spacetime is interweaved, and our universe is constantly moving, does space and time travel at the same rate? Unless that whole thing of our universe moving is only physical energy and matter and not actual spacetime as a whole.

    I might've gotten things mixed up, if so please clarify.
  2. jcsd
  3. Dec 30, 2009 #2


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    What do you mean by "travel through one of the woven fabrics?"

    We have a lot of freedom to travel through space, and we're not stuck in one instance of time (we seem to travel forward through it) so in some respect, we are traveling through spacetime itself.

    I'm not sure what you're considering "one of the woven fabrics" though.
    This is an interesting question. You might want to try asking it in the Cosmology subforum.
  4. Dec 30, 2009 #3
    What I meant is to travel, in the Sci-Fi sense, of time (past or future).
  5. Dec 30, 2009 #4


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    It's still a mystery whether that kind of time travel is possible. If it were, I don't think it would work at all like Sci-Fi movies predict it would.

    For instance, if things (including people) spontaneously arrived at particular "points" in time, or if you disappeared into the future, you would be violating conservation of mass. Since we like conservation of mass a lot, you would have to account for why we've never observed a violation of conservation of mass.
  6. Dec 30, 2009 #5
    Yeah, that's what I had gathered. I don't think instantaneous time travel is entirely possible either. Also on a different point, we've never observed a violation of the conversation of mass with all the spacetime continuum thing going on (wibbly wobbly timey wimey). My question stems from our theory of spacetime being interwoven like a knitted blanket. We could, in theory, manipulate spacetime given the technology, that's been said. My question (or hypothesis if you will) proposes that you could travel in the dimension of time. While space and time are interwoven, they are still different fabrics of the universe.

    Putting conservation of mass into play, well, what would happen if you could travel in the past or future, how does conservation of mass come in with that?
  7. Dec 30, 2009 #6


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    I'm still not very sure what you're saying. It sounds like you're taking the analogy too far.

    No clue. It has raised a separate question in my mind though that I shall now post.
  8. Dec 30, 2009 #7


    Staff: Mentor

    The problem with this analogy is that it implies that there is some "real" space or time independently of the other and spacetime is just a convenient combination of two inherently separate things. A better analogy would be a piece of paper where people can draw lines representing space and time in many different and equally valid ways.
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