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What happened before the Big Bang?

  1. May 5, 2003 #1
    What happened before the Big Bang? Was there just matter about or was there a big bang before the big bang?
  2. jcsd
  3. May 5, 2003 #2


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    Nothing was before the big bang because by definition it is the beginning of time and existance......

    I think there are some theories out there that there is a big bang, the universe expands, then it contracts untill its a singularity again, and then the process repeats itself..
  4. May 5, 2003 #3


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    Re: Re: What happened before the Big Bang?

    Yeah, "oscilating universe" model. Used to be pretty popular. Not as much now that the rate of expansion has been measured to be accelerating.
  5. May 5, 2003 #4
    Re: Re: What happened before the Big Bang?

    this scares physicists(hawkings at least), before the big bang there was imaginary time.
  6. May 5, 2003 #5
    There are actually some very interesting theories involving universes created everytime a black hole is formed and any time there is a big crunch. In other words, when a star collapses into a black hole it creates a tunnel in spacetime that opens a new universe, another big bang. This creates a multiverse. (Of course, since by definition a universe is "everything" by definition the multiverse should actually be called a universe, which is perhaps why a new definition for universe needs to be written.)
  7. May 5, 2003 #6

    unless the BB was a local event
    other bubbles with there own BB
    could predate ours

    does the increasing accelleration
    of the univerce's expansion rate
    "prove" there is something out there beyond our current "NOT YET"
    pulling us outward????
  8. May 5, 2003 #7


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    Re: Re: Re: What happened before the Big Bang?

    Before the BB: there be dragons...

    I doubt you will find many scared physicists, least amongst them Hawking.
  9. May 5, 2003 #8
    Simply explained, INVALID. This is an invalid question because we couldn't possibly know. It is like asking what is "right outside" of our universe, there is no way of detection.

    We can't possible go back and see, and our theories and such don't hold up outside of our universe, so we could only possibly know what happened INSIDE the singularity. Honestly though, what does it really matter what happened outside of the singularity or before the big bang, it has no relevance to our current universe, as long as it wasn't apart of the "big bang system", I suppose.

    SIDE NOTE: [I'm just assuming the big bang was a closed system, if it was open then it would matter what happened before or outside.]
  10. May 5, 2003 #9
    Re: Re: Re: Re: What happened before the Big Bang?

    scared of the notion of an ultimate beginning, i think so, mainly because a beginning points to a creator. im still not too keen on the specifics of imaginary time. is it infinite or finite? and how can one justify this?
  11. May 6, 2003 #10

    There was nothing before the big bang..the answer is correct if we agree "that everything came from nothing because its the only thing that do not come from anything" and if we agree to the answer that there was something (anything!) before the big bang then still its true as things are true till they are not proven worng...sOOO
    Well, its the starting point for human brian as none of us could have peeped in the period before big bang.....
  12. May 6, 2003 #11
    How can everything come from nothing, thats an oxymoron
  13. May 6, 2003 #12
    Everything came from the point of singularity, according to the BB...what was outside of the singularity and what put it there are invalid questions because we couldn't possibly probe things outside of our universe.

    Here is how I say this...wouldn't an infinite something look like an infinite nothing, and an infinite nothing in turn look like an infinite something because we have no reference by which we can judge infinity. This would mean that an infinite nothing universe would in fact have the potential for an infinite something universe:smile:

    I think I also read somewhere that the net energy in the singularity was zero, and it is also zero today, so in reality we haven't lost any energy/mass or gained any energy/mass and, since the net energy has always been/will be zero, there isn't and never will be anything here, in this way of thinking. I just read this somewhere, I'm not promoting it, because I don't know if it is true.
  14. May 6, 2003 #13
    Re: Re: Re: Re: Re: What happened before the Big Bang?

    The beginning only points to a creator because we are unable to imagine anything outside of the universe, hence, how the beginning started, but doesn't a creator also point to yet another creator? this leads you in a loop also.

    Imaginary time is infinite, moving at right angles to ordinary time. The idea of imaginary time is to keep singularities from being a point in space of infinite space-time curvature, in ordinary time. The big bang, in ordinary time, is a singularity with infinite space-time curvature, imaginary time was introduced to make this singularity, in imaginary time, a point that doesn't necessarily begin time...take the northern most part of our earth, this wouldn't be the beginning of our earth, this compares to the singularity. The singularity is the beginning of ordinary time, but not necessarily imaginery time. This no longer makes the BB a problem of space but of time.

    I hope I made this clear enough to understand.
  15. May 6, 2003 #14
    i understand imaginary time rather well, i just wasn't too sure if it was said to be infinite or finite, thanks. and yes, logically having a creator would point to another creator, yet most religions specifically note that before the "god" there was nothing. notice that if we ever come to the conclusion that the no boundary hypothesis proposed by hawkings is false, then there would be scientific proof that something started our universe from outside of our universe.

    im not exactly sure, but i believe imaginary time is simply a theory (i have no clue how someone could prove it). therefore, one must think that perhaps it's only relevance would be to make sense of a situation that doesn't make sense. this doesn't flow well with me because it seems like a scapegoat for physics without real proof of any kind. the same thing happens with the weak anthropic principle and very strange numbers such as the cosmological constant.
  16. May 6, 2003 #15


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    Re: Re: Re: Re: Re: What happened before the Big Bang?

    First, there is nothing about the Big Bang that requires a creator. Or even points to one.

    Second, so what if God created the Big Bang and has had little or no subsequent involvement in the unfolding of the universe? That is a perfectly reasonable hypothesis. Why would it scare any physicists?
  17. May 6, 2003 #16
    Re: Re: Re: Re: Re: Re: What happened before the Big Bang?

    the only reason the BB doesn't point to a creator now is because of the imaginary time theory and the no boundary hypothesis.

    well not scared in a sense of being afraid, but science just will just never accept god as the only answer, they make things logical by adding new terms and new theories. im not saying it's a bad thing, but when you continually invent new theories and ideas just to suit your previous theories i get kind of skeptical.
  18. May 6, 2003 #17


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    Scientists are stuck between a rock and a hard place.

    If they stop speculating at the point of the big bang singularity, then they are accused of being complacent and not seeing the bigger puzzle (i.e. what caused the big bang).

    If they DO produce hypotheses, someone slaps them down for "continually inventing (untestable) new theories" etc.

    Clearly, the progress that science has made in the past 50 years is far beyond what could have been reasonably anticipated before the discovery of the cosmic microwave background radiation in the 60's.
  19. May 7, 2003 #18
    The interest thing is, gravity is only a theory too, the world being round is also only a theory.

    If God created the BB this wouldn't really scare physicists, per ce,
    but it would make the laws of physics changeable, which doesn't happen. Occam's razor apply's to God in science, and as of now we don't need Him.
  20. May 7, 2003 #19
    yes, but can you observe imaginary time as you can gravity? and i far as i know the earth being round is proven :wink:.

    funny thing is that the "laws of physics not being changeable" is the no boundary hypothesis in a nutshell. if just one point in the universe has a different set of laws the whole theory crumbles (finding that one point(s) would be very difficult though, also i assume if it was proven false another hypothesis or theory would just take it's place). also if god is all-powerful it wouldn't matter what theory you came up with, god could always have created the universe just the way the theory states. it's really an endless argument that as of now shows no clear answer.
  21. May 7, 2003 #20
    What happened before the BB? 1st post

    If we consider the initial singularity of creation as defined by the big bang, it has not been considered except as a beginning. However if we attempt to consider it an interesting thing happens. We can define it quite well.
    S has no dimensions because measurement has no meaning. One cannot speak of when it initiated Reality because time did not exist. As to where S was is just as irrelevant since Space did not exist. Reality not as we know it, exist. And if we try to define its position we need a relative point for comparison. Out of luck there. So we must say it happened and Reality began, IF we subscribe to the Big Bang. Can we define it? Yes but only in relative terms, our perspective.
    Today, We hypothesize and then follow it with formal logic and then through experimentation we confirm it, once again from our perspective of reasoning.
    Prior to scientific methodology most systems of understanding Reality was sufficient. They were self limiting and were supported by subjective imperatives i.e. “The earth revolves around the earth since God ordained the world as the center of the universe”. Objectivity and proof was not an essential ingredient in the discovery of Reality. Do we understand any better now? No, even though scientific methodology has enhanced the accuracy of our explanations we cling to the system that best supports our perspective. This is only natural
    “Common sense suggests that any physical system requires physical continuity in its own spacetime.” Yes the physical infrastructure of reality and our explanation of it is necessary for us to manipulate it at will. But like the alchemists in the middle ages we only need to understand out environment relevant to our needs. Have we defined Reality correctly? Yes, for now, our math confirms it and our devices work. Was the BB real? Many theologians say so because “Out of “No thing”, not nothing, he created all creation.” The BB fits the description pretty well. And as for Math, well I’ve always wondered did the chicken come before the egg. Can pure math spawn an explanation of the physical? Can blind calculations explain reality? Fractals?/ “Its six of one and half a dozen of another.”
  22. May 7, 2003 #21
    There are two ways of looking at it-
    the observable universe that is relavent to us is the only thing that exists, or there is a "larger" universe within which the Hubble radius can fit. The escape velocity at the Hubble sphere = c, defining us as a time-like black hole. If one physically traveled there (1 Hubble radius), one would not see anything but the homogeneous, isotropic universe we see here. But if we move in so called imaginary time (freezing time and moving through the universe without moving through time, just like light) we can see the 'edge' of the universe that coincides in time with the big bang. Physicists can not determine directly if such a universe exists.
  23. May 7, 2003 #22
    Well, I wasn't sure the earth being round, it seems to be only a theory, since our space flights are debateable and some people still think the earth is flat...but I will take your word for it and assume now it is fact

    If God created the universe according to the laws of physics then wouldn't the laws have to exist before God? and therefore created God? maybe, I'm not positive about this. The problem with God creating the universe, with a set of laws or not, is that we have never observed a place in the universe that doesn't obey our set of laws, you would think, of course this isn't a sure fire way of thinking, that if God existed we would see that sometimes in someplaces the laws change, if only for a short period of time. He screwed up on man, Noation deluge fixed that, it seems reasonable to assume he screwed up on a much larger scale (with much more room for screwing up) on the cosmo's, so he would simple push that little blue spec a few light miles over to keep it in a nice tight orbit our the sun?
  24. May 9, 2003 #23
    Since we're hijacking this topic, there's a good Sci-Am article this month about the consequences of infinite space with infinite isotropic homogeneous mass (mass is a smaller infinity than space). According to statistics, there is an identical human being in an 'alternate' universe exactly like you doing exactly the same thing about 1e28 meters away. A copy of the entire universe exists 10e10e118 meters away.
  25. May 9, 2003 #24
    if god created the universe he would have in turn created the laws of physics. why would god have to create places in the universe that don't obey the same laws anyways? and im not too sure if i would call the human race a "screw-up", but if you use that logic you could easily see black holes as a screw-up, but really now, both the human race and blackholes are spectacular things.

    and schwarzchild how did they come to the conclusion that an alternate universe would have to exist? sounds like a cool idea though, can you post a link to the article?
  26. May 11, 2003 #25
    Lets see if I can find it...
    Parallel Dimensions
    Gee they're awful nice for offering their story for free!
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