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Disconnected universes?

  1. Sep 14, 2009 #1
    Dear all

    I've read that some "Multiverse" theories suggest that there are infinite number of universes .. But they are all disconnected universes.. each have its own matter and energy, own spacetime, own constants, and own laws.

    They cannot affect each other and nothing can pass through them

    I know this sounds unscientific because since they cannot affect each other, so it's impossible to detect them

    But regarding to the hypothesis itself, why these universes are disconnected? why they can never affect each other and nothing can pass through them?

    And why scientists think that these universes exist while they can never detect them?

    waiting for answers .

    thank you
    Last edited: Sep 14, 2009
  2. jcsd
  3. Sep 14, 2009 #2
    Re: Disconnected universes?

    It might be interesting to consider that Newton's gravitation model has no propagation construct. Also GRT has no propagation construct. And Hubble expansion (i.e. universe expansion) has no propagation concept. So even for in our manifold (i.e. surface), propagation would seem related to quantum descriptions, but not to manifold.
  4. Sep 17, 2009 #3
    First, I'd like to point out a petty, yet interesting fact that the term 'universe', including the prefix 'uni', implies 'one'. The discussion of "disconnected universe" needs to understand/use a term different than 'universe'. By definition, there is only one universe.

    All of those 'disconnected' universes are merely part of this one, by the definition of 'universe'. Some people of course could suggest that if they're truly disconnected, then they can't be part of the same universe. On the surface, that seems possible. However, to mind untrained in relevant areas, it would seem POSSIBLE that an elephant is a mouse. And in this case, if there is anything that is disconnected, we cannot call it a universe unless we add a new definition to 'universe'.

    The petty aside,

    The concept of 'Disconnected universes' comes from the same belief that there can be such a thing as 'nothing'.

    For one thing, since we even HAVE the concept of a disconnected universe while living in THIS universe, then these "disconnected universes" are connected to this one by virtue of the existence in both universes of the knowledge of their potential existence. Therefore they are not truly (completely) disconnected, at least in this one area, if not others.

    Many physicists are trying concoct the next level of "what is holding the ocean, in which the tortoise is swimming, on whose back Atlas is standing, who is holding up the world"?
  5. Sep 18, 2009 #4


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    It has been proposed that universes can emerge on the 'other' side of black holes. It is an entertaining, but, unprovable conjecture.
  6. Sep 23, 2009 #5
    chronos - i have been thinking about the theory you mentioned for a while and actually came across this message board in search of other people to bounce ideas off of so here goes:

    if the center of a black hole is a true singularity, is it possible that the fabric of space time becomes bent to such an extreme that it in fact can cause the creation of another "universe" (for lack of a better term) by "tearing" space time and causing the singularity to explode in a similar fashion to the "big bang" due to the extreme conditions it has created? think of the fabric of space time as a 2-dimensional plane and the black hole causing a massive infinitely long cone to be "bent" into the plane. is it possible that the plane can become so distorted that the singularity can actually become dislodged from space time in our "universe" where we witness the black hole "evaporate"?
  7. Sep 26, 2009 #6


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    Indeed. The problem I have is what happens to the 'daughter universe' when the black hole mom evaporates? I see serious conservation of energy and causality issues.
  8. Sep 26, 2009 #7
    i would need to know more about the behavior of evaporating black holes to take a stab at answering your question. one would have to measure the effects of an evaporating black hole to be able to conclude if that theory could hold any water. theoretically, if all of the matter and energy immediately transition at some point in time to the newly formed universe wouldn't the sudden "loss of mass" in our universe send an immense amount of gravitational radiation into space in a very short span of time?
  9. Sep 26, 2009 #8
    The responses to this question amuse me because over a year ago I too brought up the question of how it might be possible for black holes to actually be creating other universes. The replies I got were less responsive. In fact, I was told I didn't belong on this forum because of such questions.
    It's good to see you're now open to such queries. As a matter of fact, after I was told I didn't belong here, I further studied the possiblity and it seems there are a number of scientists who also believe the structure of a black hole could be the source of other universes.
    I also recently took a course on physics and quantum physics, so I truly hope my ideas don't offend anyone.
    My postulation may be simple. We believe that our universe was created by the big bang. Two or more particles collided at such high such speed, and created the universe. From that point the universe began to expand in all directions. Why do we assume or presume that when two particles collide creating a universe all inclusive? Isn't it possible that the big bang could have exploded in many different directions creating many other universes?
    We know that the Andromeda Galaxy is destined to collide with the Milky Way in millions of years from now because we can see its movement and expansion. I learned in physics that of all the light sources we can visibly see only a sliver. The rest we would never have been able to see if it weren't for devices that were created to see what we can't. eg... ultraviolet, xrays...etc. But isn't it also possible that there are other, maybe many other light sources we haven't been able to see because devices to pick up those lights haven't been invented yet.
    If that's the case, then how do we know that other universes aren't already colliding with ours? Perhaps we can't see what's happening because it might just be in another dimension that we can't see yet.

    Finally... my thoughts about the blackhole question. Going back to the big bang theory, we're talking about particles colliding at intense speeds. Stars or dwarfs get sucked into it's gravitational pull and collide at those same intense speeds. We know from physics that energy can't be created nor can it be destroyed, it can only be converted from one type to another. It just might be possible for these conversions to be in dimensions that are beyond what we can see. We might just need to develop new devices that will be able to pick up on those sources. It wasn't until the mid 60's ( I believe) that we were finally able to detect where the center of our galaxy is. Think of all the other light sources that just might be blocking our views into ours and other universes.
    Just my thoughts... and thanks for listening, and thanks for any thoughts you might have as well.
  10. Sep 26, 2009 #9

    http://en.wikipedia.org/wiki/Multiverse" [Broken]
    Last edited by a moderator: May 4, 2017
  11. Sep 26, 2009 #10
    That being the case in regards to hypothetical multiverses, isn't also possible that they even our universe could be merging or colliding? And as I pointed out earlier, that it perhaps we just haven't discovered or invented devices that might help us find these universes including the energy that is absorbed into the hearts of blackholes?
    Thanks again.
  12. Sep 27, 2009 #11
    the problem i have with theorizing about other universes colliding with ours is the lack of gravitational interaction within our visible universe. i would expect that two universes merging or colliding would be a tremendously violent event gravitationally speaking. however i am open minded enough to admit i could be entirely wrong and the presence of another universe within our own composed of an entirely different sort of "matter" could prove to the be solution to the "dark matter" and or "dark energy" problems.
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