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What happened before the big bang?

  1. Aug 3, 2011 #1
    So for years now, I've been of Stephen Hawking's opinion that asking what was before the big bang is a meaningless question since its like asking what's north of the North Pole. However, after watching BBC Horizon's What Happened Before the Big Bang, I have to admit that I am a little conflicted. Several scientists in the show, including Michio Kaku, seem to be of the opinion that "empty space" had existed before the big bang. This is confusing because I thought the big bang was supposed to be the origin of spacetime? Also, I recently spoke with a physics professor at a local university (guest presenter at our school) and he said that the big bang actually happened across multiple locations at once. This also confuses me because until that point, i had heard that the big bang came from a singularity. I am wondering what new evidence exists to show that the big bang wasn't the origin of space and time and what evidence exists to show that it happened across multiple locations.
  2. jcsd
  3. Aug 3, 2011 #2
    This is a meaningless question. If the big bang model is correct, you should not think of it as a cosmic explosion. It is a singularity of space and time, nothing was before it, nothing caused it.
    Some Physicists, string theorists and cosmologists posit that there is imaginary time or a multiverse, but most of these claims are unfalsifiable, or at least appear to be.
  4. Aug 3, 2011 #3
    Just to be clear, the very time was "created" in the big bang, the space also. So It is a meaningless question as pointend functor.
  5. Aug 4, 2011 #4
    at some point there must have been a big bang that created time and space but whether our big bang is that big bang is an open question

    all we can do is consider the possibilities and ask which is most reasonable

    But we will probably never know for certain what actually happened.
  6. Aug 4, 2011 #5
    I don't remember who the philosopher was (think it was from Ancient Greece). Anyway, his argument was something like: If you approach the end of the universe and throw a spear at it, and it bounces off, something has to be behind it. And if the spear pierces it then it's clearly not the end. - So if you can't logically find the end, how would you go about logically finding the beginning?

    Either way it doesn't seem "meaningless" to me... just really, really confusing and not in tune with how we conceive things currently. Sooner or later someone is going to come around with a fresh perspective and make the question/theory more fruitful. Though for now thinking about more practical matters which may benefit our planet, and by extension our species, seems like the smarter option.
  7. Aug 4, 2011 #6
    it isnt that the answer is beyond us.
    its that its the wrong question to ask.

    when we figure out what the right question is then the answer will be obvious.
    we will say to ourselves 'but of course, how else could it have been?'
  8. Aug 4, 2011 #7
    The question isn't meaningless, we just don't have a clue what the answer is. The big bang theory doesn't concern itself with anything before the event itself.

    Since spacetime originated with the big bang (did it originate at a point or everywhere at once - infinite or finite universe?, we don't know), I think the best wording of the question is "what caused the big bang", not "what was before the big bang", since the latter implies a timeline existed before.
  9. Aug 4, 2011 #8
    Best response I have ever seen. I learned, at the age of about 14, that there are some questions that you must not ask. Those in charge (with the large brains) don't have all the answers. Few will admit they don't know. Some will go to great lengths to baffle and confound others by presenting some theory that can neither be proved or disproved.

    As long as we are here, how about Dark Matter, Dark Energy, and Time. I have not heard any interesting new theories lately.

  10. Aug 4, 2011 #9


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    Well I hope you have unlearned your lesson by now.

    Some people wait to be told, while others become scientists so they can try to answer the big questions themselves.
  11. Aug 4, 2011 #10
    It apparently happened everywhere at once: the singularity is not a point in spacetime... there is NO experimental evidence about what initiated the big bang...nor what existed before it, if anything....only some evidence from after the bang, like the uniform cosmic background microwave radiation coming at us from all directions.

    Such questions ARE worthwhile....Where would we be if Einstein never asked "What happens when I catch up with a lightwave?"....that's his teenage question that later led him to relativity.
  12. Aug 4, 2011 #11
    I think that the main problem here resides in the inability of understand time like other dimension.
    We perceive the time passing in ours lives so easily that we took it for granted.
    We all know that gravity/speed changes the passing of time, but we can’t fell it, so it will require lots of abstraction to explain the things.
    First of all let’s remember what we know empirically, the back ground radiation, the accelerated expansion of the universe, the deformation of time/space and the existence of singularities. I will not explain who the experiments have been done cuz it will require much more time.
    Using the back ground radiation and the accelerated expansion of the universe we can suppose that long time ago we are much more closer, due to uniformity of the background radiation we can suppose that all the universe matter came from the same spot, but we know what a lot of matter together can do with time/space, they deform it, and when huge amounts of mater goes to the same spot we call it a singularity,( we don’t know from empirically experiments that all goes to a POINT, but the mat that fits with all the experimental data we know says it must be a POINT) so, near that point we states that the time/space is so deformed that the time almost don’t passes, (if some one manage to fall in a black hole looking away from it, to the stars, in the time fell [relative time] he will see all things that occurs after that to the very end of the universe).
    Now think that all the matter of the universe is, some how, in just one singularity, the time/space are so deformed that they don’t exists, like having 0cm in any dimension.
    Since there is no time, the question of “Before” are meaningless. It’s like asking who is in the first place of a race before the race begins, there is no first cuz there is no race, after the race starts I can tell to you.
    Now the Space problem, a nice exemplification of the universe is to think it as a rubber balloon, but let’s make it a little more accurate think of the inner tube of a tire, one torus-shaped balloon made from rubber, the universe as we understand are just the rubber part, it is finite, but you don’t find one end or (if you have a little more mat and abstraction powers) think of a Möbius strip, just a little more of dimensions ^^ .

    Sorry for the mistakes and lack of coherence English isn’t my first language and I learned it by myself.
    I tried to show in the easiest way not using the mat nor the physics needed to show in profundity, I hope that I don’t have done huge mistakes.
  13. Aug 4, 2011 #12


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    I know this isn't the thread topic but objects fall in finite proper time into a black hole.
  14. Aug 4, 2011 #13
    I dont think so.
    time stops at the event horizon.
    to an outside observer even light wouldnt be moving at that point.
  15. Aug 4, 2011 #14


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    An external observer will see time slow down for a falling observer as he/she approaches the horizon but the falling observer will go through in finite proper time in his/her reference frame. Anyways, don't want to hijack the thread =p.
  16. Aug 4, 2011 #15
    oh. ok. thats right.
  17. Aug 4, 2011 #16

    Andrew Mason

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    It is only a meaningless question if you accept certain current 'theories' of how the universe began. Those theories are built on rather slim amount of evidence and have not really been tested. (It is difficult to test cosmological theories). A few centuries ago scholars may have said it is a meaningless question to ask what occurred more than 10,000 years ago (before God supposedly did his 7 day creation thing). So don't be deterred by someone telling you it is a meaningless question. That may not be the conventional response 100 years from now.

    Having said that, yours may not be a question for which science will ever be able to provide an answer.

  18. Aug 4, 2011 #17
    M-theory kind of goes into this question by stating that there is no such thing as a unique big bang. Instead multiple collisions caused by the collision of membranes. in other words, there exist two extradimensional membranes that collide, and this collision yields big bangs. Therefore our universe is nt so special...bangs somewhere else yields to other universes.
    All theories require a cero time. Maybe someday as Andrew M said, we will find the answer for before zero time. Anyhow, God did everything. Seven days...seven years, seven millenium...who knows. Here we are and im sure pi, 0, c and several other things were no human invention. They were there, we just discover and use creativity to transform our sorroundings, to keep creating from the created. take care
  19. Aug 4, 2011 #18
    And ur question is not pointless.
  20. Aug 4, 2011 #19


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    Interesting and insightful...
    Then your cheese slips off your cracker...
    Should have quit while you were ahead...: wink:
  21. Aug 5, 2011 #20


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    Perhaps a workable theory of quantum gravity will shed some light on the issue. For now, we have no mathematical model that works for t=0.
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