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Space Inflation?

  1. Jun 9, 2005 #1
    I am not mathmatician and know little of string theory. But I am looking for God and I hear those of you who do know string theory may be hot on his trail.

    Years ago, when Hubble was still only a promise we were told it would allow us to see back in time nearly to the big bang. My concern was that unless earth was moving at near the speed of light, all the light from any where near the big bang should have passed us by long ago, never to return. I was informed that the answer to this concern was "space inflation" which moved things apart faster than the speed of light. In questioning this explanation, I was told that "space" is "not the nothing between two somethings" (as I posed, because 100 times zero or nothing is still zero or nothing and it cannot be expanded without moving the somethings), because space is not nothing, I was informed.

    Now I believe I have been told that space is made up of strings. Recently, sci.channel said the big bang was caused by a collision between parallel universes, according to string theorists. My question is: What was between the two universes before they collided? Also, even the most tightly woven fabric of "strings" has "space"s between the strings. In string theory, what is between the strings, if not space? Finally, is "space inflation" still an accepted theory?
  2. jcsd
  3. Jun 10, 2005 #2
    When I was a child I used to like toy cars. I preferred the kind that had real wheels that turned on axels so that they would roll nicely by themselves. It did not bother me that the doors and windows did not open, nor that there was no engine beneath the hood.

    Later I got into building models, and I preferred the kind that had doors and hoods that opened, revealing seats and an engine. Of course the seats and engine were just bits of plastic, but that didn't bother me. I remember one of them even had a steering wheel and linkage so that when the steering wheel was turned, the steer wheels changed direction. Cool.

    Strings, branes, and LQG are just models, not the real thing. Asking what is between the branes before they collide (it is usually called "the bulk", btw) is akin to asking why the doors don't open. It is just a model. If you want to play with it, focus on the parts that work, not the parts that don't work.

    Of course, you are welcome to try to build a better model. Later, I was interested in model airplanes, with flaps that went up and down. I even had one that really flew, with a real gas engine, but it went up, it went down, and propellers don't work well in dirt.

    As for trying to track God, well, it seems silly to me to try to track someone who knows perfectly well where you are all the time. It is like trying to track yourself. At best you only go in circles.

    If "space inflation" is a theory, I would guess someone somewhere must accept it. What difference does that make? There are still people who believe God talks to them out of cracks in a rock. Whatever.

    These are not really very interesting questions. I am sure you can do better. But thanks for being here.

  4. Jun 10, 2005 #3
    Very interesting. Toy cars and airplanes. Hmmm. No engine. No windows. Now, I get it. Very interesting. I am sure no one could do better. "The bulk." Hmmm. Nobody (except me) cares what the bulk is made of or whether it really inflates. Very interesting. Thanks a lot.
  5. Jun 10, 2005 #4
    Physics Forum is not the place to seek God. God is a belief system and as such has nothing to do with proof or science. I hope you find your God, but please don't look for 'proof' of God here. God doesn't need scientific proof, and scientific proof doesn't need God...
  6. Jun 10, 2005 #5
    That was kind of a joke, Adrian. Do you know the answer to my question or not?
  7. Jun 10, 2005 #6
    R, I have re-read your response, trying not to be blinded by your smart alecky insults. You spent some time on it, and perhaps some if it is even informative. I am guessing the above part is.

    Does this mean:

    Sting theory is in its infancy. Whether it will turn out to be the grand unified theory remains to be seen. Although it seems to explain many things, many more things have yet to be tested by it. For example, string theory does not explain why the universe we live in seems to have expanded faster than the speed of light. It does not explain whether such an expansion would violate the assumption that C cannot be exceeded. Also, we do not know what, if anything, is between the strings, branes or whatever.

    I hope I am not boring you too much. These questions interest me, and I am not sure I can do better, despite your encouragement.
  8. Jun 10, 2005 #7
    The question regarding the nature of the bulk (or for that matter, whether the cyclic Universe model is right) cannot be answered confidently until a full nonperturbative description of string theory is formulated.
  9. Jun 10, 2005 #8
    You are pretty much asking "what was there before the big bang?". Well the simple answer is that no one knows. And physics has nothing to do with God at all. It is just to strengthen our understanding of the universe, it is not about religion.

    And about all the light passing Earth.....are you serious? Do you think that if the universe is not expanding, the Earth would be completely dark? Gas would have still formed into stars. It would be no different.
  10. Jun 11, 2005 #9

    You may find some insight into what you are looking for from this book:
    Wholeness and the Implicate Order by David Bohm

    David Bohm advanced a lot of research in quantum mechanics, and was even sought after by Einstein himself to be an assistant for him. However, the book covers a philosophy that he constructed that suggested that the problem with modern science was that it abstracted a whole from the fragments, rather than the reverse. While string theory is not mentioned in the text, his theory is relevant regardless, because string theory still follows this approach of abstracting a whole from the fragments (strings or branes).

    What would he say is between the strings? As some have already pointed out, asking that question is pointless within the context of the theory. It's like trying to ask what's between 1 and 2 if I tell you there are only integers that exist. Or, it's like trying to ask what's between each frame of a movie at a theater? That question is irrelevant, as long as you start from a frame that begins in fragments - ie, as long as you are wondering why the picture on the movie screen appears to be moving, instead of just taking it as moving. You are trying to extend the theory beyond what it's meant to be used for. And, as is generally the case, you get answers that don't make any sense - just like getting infinities when constructing theories of quantum gravity.

    I'm not saying I completely agree with Bohm, but he makes a valid point. You should give it a read if this question troubles you, because it will shift your focus to help you understand why you are asking it in the first place.

    PS: God has no rational basis in science at all. There is no meaning in the physical universe, and looking for one is as useless as trying to find what's between 2 things by starting with them. I'm a firm believer in making meaning for yourself, because that's the only one that can exist. And if you are looking for a way to justify your own meaning externally, you may be disappointed in finding that you simply can't. So, if you believe in God, do so, but don't seek to prove it. And if you must prove it, you must accept abandoning it, because that is the inevitable result.
  11. Jun 11, 2005 #10
    I am very sorry, SamCJ, that you take my meaning for insult. I honor and respect your quest for answers. It is the best of what makes us human. But really, it is just a model. String theory describes something that happens in places we cannot see.

    I think you should read and study to satisfy your curiousity. There are many popular books now, some of them very good reading. I am currently reading Roger Penrose, Complete Guide to the Laws of the Universe, and find it helpful to me. Unfortunately to understand the model builder's art you really have to know a lot of math. Personally, I am working on that.

    I hope you keep looking. The world is full of meaningless distractions. I would be glad to help you if I could. But, to expand upon the image another poster has placed here, what is between the frames? Celluloid, air, an imaginary image halfway between the two frames? What does it matter? We are really and legitimately interested in the story line, not the mechanics of cinematic projection.

    Brian Greene, Lee Smolin, Roger Penrose, many others. Once you get the basics, you can try to keep up with current work on arXives.

    One piece of advice. Don't put too much faith in humans or their gods. Better keep your eyes on the hard facts.

    Thanks for being here,

  12. Jun 12, 2005 #11


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    SamCJ, I think you misread Richard. It is not his nature to be denigrating. He is fond of using analogies and sometimes folks who are not familiar with his style take it the wrong way.
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