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The big bang help!

  1. May 13, 2010 #1
    alright so my freind was telling me about the big bang. anyways he was saying that it all came out of some black hole or w/e and i dont really believe him. my parents say that its not possible that the universe was made a million years ago so i dont know wat to believe. i mean i took phycical science in school and it was right before my religeon class and they always told me it was just a thery. even if there was a big bang it doesnt make sense that all that stuff would just come out of nothing. you gotta have some1 there to start it like god or something right? i mean a picture doesnt paint itself so how does the universe start itself? also if you see a watch you know that it has to have been made by some1 to right? theres no way that a watch could randomly come together out of nothing. so im realy confused and im really curius. help?????????????????????
  2. jcsd
  3. May 13, 2010 #2


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    They're right. It was a lot longer than a million years ago.
  4. May 13, 2010 #3


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    The current state of our knowledge is that the universe began 13.7 billion years ago. It eventually cooled, and then galaxies, stars, planets and people eventually formed. There are piles of evidence to support this. Anyone who says it is "not possible" or that it is "just a theory" is either ignorant or being intellectually dishonest.

    The rest of your questions seem philosophical in nature and probably are best not discussed on a forum about physics. However, I will point out that the watch maker / painting arguments are just silly. There are plenty of examples of complex structures that can be formed without design. Mountains for instance. Or galaxies or stars. The list goes on.
  5. May 13, 2010 #4
    U should read some of Stephen Hawking's books, no one has a clearer picture about this matter than him...... Now to your question there are no definite answers and to know the definite answer is beyond our limitations...the idea of big bang came from the observation that all the galaxies are moving away from each other(Edwin Hubble's obs'n) and if we go back in time it'd appear as if the whole universe started from a point and then expanded, but at this point which is of infinite density, all laws of physics break down thus eliminating our predictability....many satisfactory observations have ensured the existence of a big bang, but what led to the big bang no one can say ....u may believe in a creator but he can't be god, even he must have limitations.
  6. May 13, 2010 #5
    I'm not sure if I detect a troll here.

    I can never tell with people raised by creationists whether they are being serious or not. The same phrases like the watch and the painting, come up time and again. I find it impossible to tell if they are being ironic or serious.

    My prediction is that this will deteriorate very quickly so: IBTL.

    EDIT: I really hope I am wrong, and you actually are here to gain knowledge on the big bang. As it's perfectly acceptable to have a faith (If indeed you do believe in a god) and believe that science is the very best mechanism for telling us how everything works.
    Last edited: May 13, 2010
  7. May 13, 2010 #6


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    The initial blackhole is a bit of a sticking point for the Big Bang model. It is derived from the fact that enough matter exists within the universe for individual black holes to exist; therefore, all the matter in the universe gathered into one spot would necessaerily be a black hole. Since objects inside a black hole cannot move outward away from the center, the BB model appears to lead to a paradox.

    For most theorists, the weight of the evidence in favor of the model remains overwhelming.
  8. May 13, 2010 #7
    Thanks for the help
  9. May 13, 2010 #8
    I am still real confused tho
  10. May 13, 2010 #9
    It's also a bit of a misnomer calling it a black hole. As that is a stellar body within spacetime. This was a singularity of spacetime itsself, so the rules don't apply in the same way.

    So the start of the universe was not a black hole, merely a singularity.

    The problem is, we can only look back and devise experiments that go back to a time after the inital event. I think the shortest time we know after the inital event is on the order of 10^-40 seconds (or something like that), before that we don't really know what happened, and can't currently think of an experiemnt to find out. However they are smart people and will work it out eventually.
  11. May 13, 2010 #10
    Perhaps a good starting point would be an outline of what the Big Bang theory _does_ purport to describe. After all, it is necessarily problematic to agree or disagree with a model or theory if you don't start off knowing what it actually intends to express.

    Marcus had a link in his signature connecting to to an excellent(!) article from Scientific American called Misconception About the Big Bang. Unfortunately this link is no longer valid, and Scientific American charges a considerable amount of money for a direct download of this article from their site.

    Now, keeping in mind that my purpose in directing the OP to such an article is not necessarily to be persuasive in terms of the validity of Big Bang (however, I think it goes a long way in that direction, personally), but rather to simply lay out what this model does and does not express.

    With this in mind, perhaps suitably expert individuals might suggest some links to pages that accurately and lucidly express just what Big Bang does and doesn't purport to describe.

  12. May 14, 2010 #11
    I have heard many stories about the big bang theory. I believe we had a big bang because the evidence is there. However, I have found zero credible evidence suggesting that was the only beginning of our universe as most all is based on if??. We only have the technology to theoretically look back in space 18 billion years ago as that is how old the light is supposedly and there are plenty of galaxies there then. String theory, Membranes, Donuts, dimensions etc. We know so little and we all have so many questions. I love this subject and it is clear, the more answers we have, the more the questions become exponential. Personally, I like the multi parallel time/dimensional continuum theory the best of which I just made up, but it sounds cool.
    Truthfully, I do love this subject, I just have not found an answer yet that passes the test.
  13. May 16, 2010 #12
    What specific part are you really confused about?
  14. May 16, 2010 #13
    What exactly does this theory of yours suggest?
  15. May 16, 2010 #14


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    Discussion of personal theories is not allowed on PF, so it is probably not best to ask.
  16. May 17, 2010 #15


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    This phrase is only used by people who have completely misunderstood what a theory is. A theory isn't a guess that might be true. It's a set of statements that can be used to make predictions about results of experiments. The predictions can be good or bad, but it's only if they're good that we consider the theory to be a good theory. Evolution is definitely a good theory. To dismiss it because "it's a theory" makes as much sense as dismissing the idea that stuff you drop will fall to the ground because Newton's theory of gravity is a theory.

    So don't buy into the "it's just a theory" nonsense. Evolution is a fact, and the theory of evolution is what explains it.

    Remember this: If it makes predictions, it's a theory. (That's why "God did it" and "there's a god" aren't theories, but "the Earth is round" is). If the predictions are accurate, it's a good theory.

    That argument is illogical. If everything needs to be started by something...(I'll let you figure out on your own how that sentence ends).

    This argument is a straw man. The parts of a clock don't reproduce, they don't mutate, and they don't interact with each other in any interesting way. So clock parts are very different from living things. Different enough to make the watchmaker argument completely irrelevant. If you want to understand this better, I recommend the book The blind watchmaker by Richard Dawkins.

    If you have questions about evolution, you can post them in the biology section of this forum, or e.g. at forums.randi.org. You can also check out http://www.talkorigins.org/. See the FAQ section. Perhaps your questions have already been answered there.
    Last edited: May 17, 2010
  17. May 17, 2010 #16
    Actually, I did not make up the theory and it is self explanatory to sum degree, but it is not mine. What I made up was "that I liked it the best". There are so many good theory involved in this subject it is hard to pick just one. Clocks dont last forever, their parts corrode and wear out, thats not a stretch to call that a mutation as it wears out and eventually disintegrates. I dont have the answer here, but I do have my own theory (yes a real theory, and not just speculation) that I would not put up because of the rules. But this question of the big bang is a hard one to over come today (mainly because of moore's law and computational capability limitations). How do you make something from nothing?
    Many think that is what the big bang implies, which actually is does not at all. This is one of my favorite subjects of all.
  18. May 17, 2010 #17
    I'd just like to take a marginally different approach to this. I wouldn't consider the earth is round to be a theory as it's not a model with any predictive powers, also we know it is becuase we've seen it is.

    The statement "The earth is round" is a fact. The theory of gravity explains why it's round.

    Just like gravity is a fact, it's the label we give the force that makes things drop to earth. The theory of gravity explains the fact.

    Just a different take on the nomenclature.
  19. May 17, 2010 #18
    I do not understand why the rules would not let someone put forth their own theory if they are willing to take full responsibility of doing so. Maybe by that theory, we all might learn something new, it might help expand our views and ideas, it might give us a different perspective towards the way things work. Can someone at least give me one good reason why one cannot put forth a theory?
  20. May 17, 2010 #19
    As a rule only 'mainstream' theories, i.e. ones that are well founded amongst the scientific community are allowed. There are regualr discussions about new theories that go against the current popular one, but no unsubstantiated claims are allowed.

    It's basically to stop crackpots from saying anything they want under the guise of 'it's my theory'. You can discuss your own theories if they are backed up by evidence in Independent research (I think thats the subforum) if you want.

    So for example: if you are a scientist conducting new research into a field, and have a hypothesis that you are currently testing out. Thats fine, as it's being conducted in a scientific manner.

    Someone coming on who is essentially a layman, who isn't really doing any research and is just saying "Hey, what is this is the case" isn't. As it's not a claim with substance, it means that you spend more time arguing about some speculative crap than real science.
  21. May 17, 2010 #20
    Ok. I see what you mean. Thanks xxChrisxx.
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