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Wormholes, parallel universes, negative mass

  1. Oct 23, 2007 #1
    Hi. I have a few questions.

    Is it theoretically possible to build a wormhole to a parallel or baby universe? Could a sufficiently advanced civilization do this? Could negative mass play a role in it? Could something else?
  2. jcsd
  3. Oct 23, 2007 #2
    I think if we can answer these questions, we would know a lot more about our universe. As far as I know, there are some calculations which show that the existence of a wormhole to a parallel is indeed possible (Hawking,...).

    However, it's not that easy... I assume that we must use a enormous amount of energy to create such a wormhole. Therefore, the physics in this environment will be a lot more complex than it is here on earth.
  4. Oct 24, 2007 #3
    Nobody knows what happens in the singularity of a black hole.
  5. Oct 24, 2007 #4


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    We do know that it would require a time machine to build a wormhole classically. There's a quote about this from Thorne that I can probably dig up if pressed, it's in his semi-popular book Black Holes, Wormholes & Time Machines, which also has a reference to the peer-reviewed paper that derives this result. I don't know if "baby universes" were even considered in this paper (probably not).

    Thus most papers on wormholes (that I'm aware of, anyway), focus on finding a "quantum wormhole" and keeping it open, rather than building one.

    If you want to look at the professional literature on wormholes, you might start with the Moriss-Thorne paper,

    http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=AJPIAS000056000005000395000001&idtype=cvips&gifs=yes [Broken]

    though you'll most likely need to go to a library to get access to it.

    If you are interested in semi-popular works, I would recommend Cramer's "Alternate Views" columns, which are available online, see for instance


    We also know that it will take exotic matter (what you probably mean by negative mass) to hold open a wormhole throat.
    Last edited by a moderator: May 3, 2017
  6. Nov 9, 2007 #5
    Different constants

    But wouldn't a parallel and/or a baby universe have different physical constants and vacuum energy from our universe? Thus, wouldn't we be destroyed once we entered the other universe?
  7. Nov 9, 2007 #6


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    It's not particularly clear how to translate "baby universe" into an exact mathematical form where the question might be answered.

    There are other issues relating to what "different physical constants" might mean, for that matter. If we take a specific example, "What happens if we open a wormhole with two different values of the fine structure constant on each end", this is not a topic which GR could address as it is not a complete theory of quantum gravity. I don't think current quantum gravity is advanced enough to answer this question, either, but I don't know that area very well.

    The topic of 'different physical constants" comes up a lot, for an interesting but rather long paper on it see


    I'll quote one view that I have some sympathy with, note that the three authors of the above paper each have differing views:

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