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Which came first QM or GR?

  1. Sep 13, 2006 #1
    Which came first Quantum Mechanics or General Relativity?

    Or to rephase it another way,

    Which came first Hawkings radiation or the Big Bang.

    Why did the singularity or blackhole, which we assume caused the big bang, not simply evaporate instead of exploding, as currently accepted?

    Regards

    Terry Giblin
     
  2. jcsd
  3. Sep 13, 2006 #2

    selfAdjoint

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    The big bang was not caused by, or accompanied by, a black hole.
     
  4. Sep 13, 2006 #3
    This is true, but since I do not accept or believe in the big bang does it matter. The singularity which is meant to have caused the big bang, must have created an event horizon of sorts.......

    The question still remains which came first Quantum Mechanics or General Relativity?
     
  5. Sep 13, 2006 #4

    chroot

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    What are you talking about with all this black hole and singularity mumbo jumbo? Please remember that idle speculation is not welcome on this site.

    Do you just want to know which theory was invented first, QM or GR?

    The two fields developed in rather similar time-frames. The first paper on general relativity was published by Einstein in 1915. The first glimmer of quantum theory was seen by Planck in 1900, but the first real formulation of quantum mechanics recognizable by modern standards was the matrix mechanics published by Heisenberg in 1925.

    - Warren
     
  6. Sep 13, 2006 #5

    EL

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    We don't know if Big Bang started out from a singularity. The singularity is an artefact of GR, but since we know GR cannot hold at the very earliest times (since GR isn't compatible with QFT) we can only speculate about it at this moment.
    And anyway, the Big Bang singularity araising in GR isn't quite the same as black hole singularities.
     
  7. Sep 16, 2006 #6
    Dear chroot,

    thank you for your history lesson, but I was asking a serious physics question.

    I have expressed my own options several times, in the past.

    [link to crackpot theory deleted - Zz]

    But I am now simply trying to continue a serious conversation, which I started last week discussing the Fundamental Structure of Space and Time.

    http://www.newton.cam.ac.uk/webseminars/pg+ws/2006/ncg/ncgw02/0906/penrose/030-frame.html

    Following a previous discussion started last November.

    http://www.newton.cam.ac.uk/webseminars/pg+ws/2005/gmr/gmrw04/1107/penrose/

    When was the last open and frank discussion regarding the fundamental principles in maths and physics.

    If science is described as the tree of knowledge, but we are only allowed to discuss each individual leaf, we will never discover if there was a problem with the roots of the original tree. Sometimes it is better to look outside the box.

    In light of the new discussion, can I ask the very important and serious question, which came first QM or GR and I don't need a history lesson, I simply wish to discuss the maths and physics implications.

    Regards

    Terry Giblin
     
    Last edited by a moderator: Sep 16, 2006
  8. Sep 16, 2006 #7

    Gokul43201

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    Since QM and GR are both manmade tools for modeling nature, the only answer to this question is a "history lesson".

    If your question is different from "which of these tools was first developed", please be clear about what exactly you are asking for an answer to.
     
  9. Sep 17, 2006 #8
    The question is nonsense. Neither theory 'came first'. Nor did they 'come second'. The 'singularity' is probably not a 'real' entity; it's an artifact resulting from the incompleteness of both QM and GR.
     
  10. Feb 16, 2010 #9
    Unlike most on this thread I think I understand your question. I think you are using the theory that once the universe has expanded as far as it can it will contract until it becomes a singularity and then will explode to create another universe, theoretically a process that will continue for infinity.
    The answer as to why the singularity explodes rather than dissipates with Hawking radiation is because it has nothing to dissipate into, being that space no longer exists, only the singularity.
    If this theory is correct though, I am still waiting to hear an answer as to why the singularity becomes so unstable it finds itself in a situation where it needs to explode,.
     
  11. Feb 16, 2010 #10
    Terrible awful thread from 4 years ago. The question is a history question, that is the only way it makes any sense whatsoever. This thread sucks, why is it not locked or (preferably) deleted. What a waste of my life.
     
  12. Feb 16, 2010 #11
    lol, cheer up..maybe the big bang theory is a waste of everyboys life lol.
     
  13. Feb 16, 2010 #12
    Well I fell into a bad mood upon reading, "This is true, but since I do not accept or believe in the big bang does it matter." :bugeye::grumpy::uhh::mad::cry:
     
  14. Feb 16, 2010 #13
    You can disagree with some aspects of the big bang, fine. But to say you do not believe in the Big Bang is just nonsense. It reveals a complete, utter and nearly all encompassing incompetence on the part of the issuer of such a statement. From Wikipedia:

    "As used by cosmologists, the term Big Bang generally refers to the idea that the Universe has expanded from a primordial hot and dense initial condition at some finite time in the past (best available measurements in 2009 suggest that the initial conditions occurred around 13.3 to 13.9 billion years ago[3][4]), and continues to expand to this day."

    If you are going to disagree with this in a public forum of physicists, then you had better have some groundbreaking argument in favor of such a position. Or at the least, be bold enough to show your support for one of the alternative ideas, and their consequences.
     
  15. Feb 16, 2010 #14
    Well I hate to depress you further but I only accept the "big bang" as a theory not fact. Too many unanswered questions for me to accept it as fact.
     
  16. Feb 16, 2010 #15
    Ok but there is no fact in science. What is your alternate hypothesis?
     
  17. Feb 16, 2010 #16
    I will accept this as fact when someone can tell me where this "primordial hot and dense initial condition" came from, or do physicist's believe it was put there by a "god".
     
  18. Feb 16, 2010 #17
    Does fried chicken taste good even though I don't know why?
     
  19. Feb 16, 2010 #18
    For anybody to give anything resembling a good answer to that question they would have to have a greater understanding of matter and energy than anybody currently has. I sit squarely in the "I don't know" corner, but I think that matter, antimatter and time are crucial ingredients in understanding this universe, in a couple of weeks the LHC will be colliding at 7 TeV, maybe that will give a good insight to everything, maybe not.
     
  20. Feb 16, 2010 #19
    I think we agree more than we disagree actually. Can you agree that
    1. the visible universe is currently expanding
    2. following from 1, as we begin to go back in time that means the universe was smaller than it is currently.

    The cosmic microwave background is pretty darn convincing to me that this expansion has been going on for roughly 13 billion years. Whatever happened before that is significantly less clear to me. But can you see how our discussion depends heavily on what you mean by "Big Bang"? The point I was originally trying to make is that there is significant evidence that the universe has been expanding for roughly 13 billion years. That is a huge part of the idea of the big bang, so when you say "I don't believe in the big bang" you are making a massively sweeping and general statement.

    I don't take anything to be fact. I certainly don't take the idea of inflation to be "fact". I don't deny the possibility that better ideas will come about. I believe that to make statements regarding the universe before the time of decoupling, you are quickly getting into very murky waters. And I am really definitely not saying the universe was at any time a mathematical singularity.

    I just believe strongly that the universe has been expanding for some time, probably a very very long time, probably for 13 billion years.


    Edit: Perhaps you would like to say what you mean when you say big bang. Also some mods will not like us carrying on this kind of discussion in this thread, but maybe that will bring about my original desire anyway :).
     
  21. Feb 16, 2010 #20
    You are putting words into my mouth, I don't believe that I have said "I don't believe in the big bang", I merely say that I only accept it as a theory. There are other explanations for redshift other than expansion and with current theory, the speed of expansion is increasing which I find hard to accept, an increase in the speed of expansion would require an enormous amount of additional energy, which from what I can make out is supposed to be sourced from a mystical material called "dark matter", it sounds all very much like hokus pokus to me, and all very unscientific.
    I believe that once the universe was alot smaller than it is now, but I don't believe there is any undeniable proof that the speed of expansion is increasing or even that it is still expanding, and I don't believe there is any proof the C is constant throughout the universe.
     
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