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Universe structure, movement, creation/destruction

  1. Jun 4, 2012 #1
    Hi everyone! I find my way here on google frequently when I get some idea and want an answer, but I haven't been able to find any answers to a few questions I have. I hold no formal knowledge of astronomy or physics, so be understanding if my questions seem inane. I always find answers to my questions and these are being asked in all seriousness. The fact I can't find answers makes me even more curious to get them! So, get ready for a long one. I really appreciate anyone who decides to take the time to consider what I say and gets back to me.

    Check out these two videos on youtube about flipping a sphere inside out.


    At :30 in the first video, the material is described as being, "an abstract elastic material, that can stretch, and bend, and pass through itself, but you cannot rip or puncture this material." Is this in anyway similar to what the fabric of the universe is thought to be? Is it a possibility?

    At about 1:30 in the first video, they show the full process, and then break it into parts over the rest of the 2 videos. What I'm wondering is if this could be a reality for what the structure, movement and destruction/creation of the universe is like. From what I understand, the universe is largely expanding, but on smaller scales it is contracting. The actions leading towards the flip of the sphere show these expansion-contraction motions happening at the same time. Seeing this as the universe, it would make its motions a sort of "breathing" in and out that continually destroys and recreates itself.

    At 1:40 of the first video, it largely collapses on itself and then presses outward. If we view this as being the universe which contains matter, then isn't the matter inside being compressed and put under such pressure that it would explode, similar to the idea of the big bang?

    Moving a bit away from the videos, I have a question about the relationship of moving matter and the space-time fabric. Using the blanket and marble analogy, I want to know what the rotation of an object does. On the blanket, I can set down and rotate the marble. The fabric sinks from the weight of the marble, but is undisturbed by the rotation of the marble because they are two separate objects. Is a planet separate from the space-time fabric, as the marble and blanket are? Or is it better to see the fabric as a spider web, where the fabric and planet are stuck to, or in some way a part of/connected to, each other?

    If the idea of the fabric of the universe fits to the materail in the video, the fabric and planets are not separte, and the rotation of objects pulls the spider web fabric, then a few things seem they should be true:

    The forces caused by rotation would pull objects closer together until there was a massive single object rotating. The condensed mass would have strong a rotational force that would eventually overpower the over-arching force from expansion, leading to the universe contracting, being destroyed by compression, and then, by the immense interal pressure and energy, flipping inside out to recreate itself.

    Again, thanks to anyone who takes the time to get back to me on this! And mods, please move this if it's in the wrong section. I apologize if it is.
  2. jcsd
  3. Jun 4, 2012 #2


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    There is no such thing as the "fabric of the universe". Spacetime is described by a metric, which is a mathematical way of figuring out the topology of something. While the works exceedingly well at finding things like the curvature of an area of spacetime, it in no way says what spacetime may or may not be made of.

    The universe as a whole is expanding, which just means that the distance between all objects not bound to one another will increase over time. On small scales, such as within galaxies or the solar systems, the universe is neither contracting nor expanding. The most accurate descriptions is very complicated and involves a lot of math and the use of General Relativity.

    I believe that what you are describing is known as "Frame Dragging" in General Relativity. See here: http://en.wikipedia.org/wiki/Frame_dragging

    This is incorrect. Frame dragging does not pull objects to a large rotating mass but causes them to spin when viewed from a frame of reference that is not rotating with respect to the background star field.
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