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Black holes and the Big Bang

  1. Apr 28, 2006 #1
    Black holes and the "Big Bang"

    Hi guys. I'm pretty new to this forum and wanted to talk about something I have been thinking about for a long time. Please note that I've only taken 100's level College physics and am by no means an expert on the mathematics involved with black holes and FTL travel, so please be gentle when you rip my theory apart...

    A while ago, I read a book called "Reverse Time Travel" who I can't remember who the author is. Basically, the book explained that if you manage to travel faster than the speed of light, you'll begin to move backwards in time. From some of the other posts I've seen on this forum, this seems to be generally accepted as correct. One of the ways that this type of behavior can be seen is inside the event horizon of a black hole.

    Let me switch gears for a second and also talk about the "shape" of the Universe. I've always liked the "subtract a dimension" approach to explain how our universe is like a giant bubble that exists in the 4th dimension of time (or the 3rd dimension once you subtract).

    Gravity is represented on this bubble by pushing it on it. The harder you push on the bubble, the bigger the indentation, and the more nearby objects are affected by it. In addition, the more you push, the more TIME is affected (because the distance between the "universe" at the pushed in point and time = 0 (the center of the bubble) is less than for the rest of the universe.

    Given a large enough gravity field, would it not be possible to have a "dent" or indentation so deep that it actually went back to Time = 0 (The beginning of time and the exact center of the bubble). Isn't this what a black hole is?

    Would this explain what happens to matter and energy that is sucked into a black hole? Wouldn't this also explain what caused the "Big Bang?" Maybe this is why there are no "white" holes... the beginning of the universe (Time = 0) is the ultimate "white" hole.

    Basically, my thinking is that all of the matter and energy released at moment of the "Big Bang" is actually the exhaust end of all of the Black holes that would ever exist in the future of the universe (from Time > 0). So it would be more like the "Big Dump" than the "Big Bang."

    Well, like I said, I'm kind of an amature at this stuff, so I'm curious what the you knowledgable types think of my idea.

    *anxiously awaits Nobel prize* :biggrin:

  2. jcsd
  3. Apr 28, 2006 #2


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    Amazon.com does find a listing for "Reverse time travel"


    I've never heard of the publishers (google finds a hit, but the company in question went out of buisness in the 1890's when the owner took the money and ran, so it can't be the same company).

    Basically, however, the information in this book is no good.

    As far as your personal theories go, you should review the PF guidelines. We do not discuss personal theories here.
  4. May 1, 2006 #3
    Err... Ok?

    That was a bit contrite.

    Sorry if I broke forum rules about personal theories. I was simply asking if my idea made any sense...

    Are you saying that the idea that particles in a black hole AREN'T going backwards in time? (Basically, the radius of a black hole is measured in time, rather than space?)

    I've heard this idea other places than this book. In these forums for example (when people were explaining black holes to n00bs, which is what I am).

    I honestly expected a somewhat nicer response from this community... Even if it were to tell me that I was completely wrong, to at least explain why.
  5. May 1, 2006 #4


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    Time moves forward in a black hole, not backward. Particles in a black hole are in a deep gravity well, so deep that they are cut off from being able to connect to anything outside the BH.

    The theory of black holes is contained within Einstein's General Relativity (GR). It is not possible, within the framework of GR, to accelerate a particle faster than c. So the kinds of ideas you are speculating (traveling backwards in time) are not accepted.

    Most of us here will recommend that you start from the point of view of what is generally accepted before you spend a lot of time investigating what is not accepted. For what I hope are obvious reasons... but please do not think that means that original ideas are not encouraged.

    However, it doesn't really make sense to come up with new ideas that are contradicted by known experiements. For example: General Relativity is needed to explain the proper operation of the Global Positioning System. The fact that the GPS works is evidence that GR is a good theory. New ideas should come with ways they can be tested. Ideas that are not falsifiable using the scientific method are rarely of any use. Most of today's physics has been subjected to rigorous testing. But there is always room for another good idea. :smile:
  6. May 1, 2006 #5


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    There is some serious physical speculation about the possibility of time travel within the context of General Relativity, but it does not involve going "faster than light".

    Plugging faster than light numbers into SR, for instance, doesn't directly cause time travel - it causes hard-to-physically-interpret imaginary numbers to occur in the Lorentz transforms.

    There are some more complicated scenarios that can cause time-travel effects with FTL travel, but they involve using at least two different reference frames, not just one.

    The idea of using wormholes for time travel is probably the best studied theoretical possibility as far as time travel goes. Some popular factual but speculative articles on this topic by a physicist (John Cramer) are:


    This has been discussed a bit in some other recent threads on "time travel" as well.
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