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Questions regarding the Cause of the Universe

  1. Feb 13, 2012 #1
    I have read a few posts and threads in here regarding the orgin of the Univers and also the big bang (BB). Some of the posts seemed to get a little heated. I am merley looking for clarification and honest dialog and input.

    First off I am a philosopher and I follow science so I tend to attack these ideas from both points of view and I spend time combining them. It is tough sitting with philosophers that know very little about science, and conversely I get a similar feel from the science end. Please bear with me as I work with the two. I really believe philosophy is science in as much as philosophy is thinking and our brains seem to follow quantum mechanics, network theory, biology, etc. all of which are in the realm of science.

    Anyway. continuing on from some previous threads. I need to know if the current theories support a t=0. My understaning is that in quantum mechanics we cannot have a zero point sum. ( i believe that is the term) There is no point in which a particle can have a specific speed and location at a specifiv time. The particle actually moves a bit like a pendulum crossing states but never at a zero point at any given time. The only equations, theories, ideas, we can fully say MIGHT have a t=0 (or t=x) is the BB. Before that point we have to use imaginary time on a vertical axis to time (on the x axis) So discussions about "before" the BB are always in imaginary time.

    eg. A false start in football is decided on an arbitrary measure of time decided by humans (philosophy) Once the players are set the ref decides at some point in his mind that any movement by the offense would be a false start. With the movement being the cause of the penalty, defensive movement etc. BUT, my understanding is that mathematically, if you were to create an equation of the situation, you could run the equation backwards and forwards with no regard to cause and effect. In fact the famous philosopher Bertrand Russel thought that Cause and effect should be changed in science since it is a human interpretation and possible misunderstanings etc. (sorry, thats another topic)

    So here is the idea I am trying to clear up and I am not sure if the math or physics support this.

    If we cannot delineate a specific point in time x (due to quantum fluxuations) then we cannot say A caused B, because we could argue the Z caused A which Caused B. This goes to First Cause. Since my understanding of Cause and Effect take into account Time then the first cause would be T=0. Before T=0 time does not exist, therefore by my definition of Cause and Effect (at point t=x A caused B) The only point in space time that we can say was a cause is the BB. The BB had no cause since there was no time before it, and cause and effect need the time component. The BB was THE cause and that false start in football is point ZZZZ billions of years down the road.

    The understanding of this would be to go to philosophy and realize our minds and conscience have evolved to understand our world. A 3-d representation of surroundings and places that we must interpret in order to survive. We have learned to think cause and effect because we learned to interpret that a crouching tiger was about to pounce and the effect would be that we are eaten. (or our best friend who just could not run as fast as us)

    K. That was a lot. but its a start.

    So, is there a t=0?
    Is my understanding of the quantum fluxuations close in regards to delineating a specific point in time?
    Is there a definitive mathematical "cause and effect"?

    other ideas?
  2. jcsd
  3. Feb 13, 2012 #2


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    Unfortunately there is currently no way to observe T=0 even if it could happen. The current standard model of the universe, the Big Bang Theory, effectively breaks down before it can reach that point in the past. So I think the only correct answer is that we don't know if there was a T=0.
  4. Feb 14, 2012 #3
    The idea of t=0 is implied from extrapolatging General Relativity (GR) to the sub atomic level. An extrapolation which I think no one trusts.
    Incidentally does anybody trust the extrapolation at all?
    We need a model of quantum gravity and we dont have a well veirified one. One popular model is Loop Quantum Cosmology which implies the big bang is not the beginning, instead there was a big bounce. Quantum corrections to Einsteins equations give rise to a replusive force when one gets very close to the PLanck scale, hence there is no t=0.
    Read here:
    Another popular idea is eternal inflaiton. In this idea the big bang is simply one of many and there are many more to come and many more before ours. The originators of this model Alan Guth and Alex Vilenkin have argued its eternal to the fututre, not eternal to the past, but this has been disputed by Agguirre and Graton. But either way big bang is not t=0 in this model.
    Read here:
    Less popular ideas include Penrose CCC model where the unvierse re scales itself at the end of its life
    and the Ekpyortic model where colliding branes in a higher diomensional space cause the big bang :

    There are of course other ideas. Maybe one fo the above is right. Maybe none of them are. Only if we can get data to decide between them will we know and that hasnt happened yet. The bottom lines is we dont know what happened in this v early period of its history and the idea of big bang is t= 0 is outdated.
    Last edited: Feb 14, 2012
  5. Feb 14, 2012 #4


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    I think you've got this backwards: they showed that spacetimes eternally inflating to the future cannot be past-eternal. See, for example:

  6. Feb 14, 2012 #5
    Yes sorry that was a typo

    Ill amend the OP
  7. Feb 14, 2012 #6
    Thanks for the help. This does allow me to ammend the argumentation logic that if t=0 then the big bang would be the cause rather than having a cause. However if t is never 0 then it could be argued there may be a prior cause, however i can still see some philisophical argumentation to cause and effect. Perhaps in a clearer definition of the two and my hope is in a mathematical sense. But, my understaning is that, even in a mathematical sense, cause and effect are arbitrary circumstances that we as humans assign to explain phenomenon.

    So if t is never 0 can we mathematically say that t=x and assign it to a specific quantum state? As i recall this is not possible so we are stuck with probabilities, wave functions, p-branes etc. So that we say at t=x (an arbitrary human distinction) then this particle,(molecule, macroscopic object, etc) is probably in this state.

    if so, then the idea of cause and effect is more of an art form. Back to the false start analogy. The ref must decide "okay, everyone is now set. Oops that guy move, so its a false start"

    Perhaps if there was a quantum mathematical structure for time?!?!
  8. Feb 14, 2012 #7
    oh, thanks for the reading. I gave them a quick skim and will get more into depth with them. The initial ideas are intriguing, but as with all of these ideas, a lot more questions arise. At least it is fun to chat about at the bars or coffee socials.
  9. Feb 15, 2012 #8


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    Bootstrapping anything into existence from first principles is enormously difficult. For now, we must settle for 'we don't know'.
  10. Feb 15, 2012 #9
    This is why I also like philosophy. We take some of these concepts and use them in thought experiments, or modify them to try and find new ways of thinking, or to see the limitations of our thinking. Many times I think that the secrets of the Universe are beyond our evolutionary ability to understand because we evolved to make sense of the world around us, not galaxies, planets etc. Nice that genetics is catching up and we can start neo-evolution so that eventually we may develop a new form that will understand these concepts, or even see concepts that we cannot even imagine due to our limited biology.

    Thanks for the help.
  11. Feb 16, 2012 #10
    Relativity says time and space must be merged into spacetime, they can not be separated.
    Spacetime does not change, does not evolve, does not start, end or move. It has no cause or consequence.

    Is spacetime the whole story?
    Quantum theory would definitely say no,
    space and time and spacetime being macroscopic concepts not valid on the quantum scale.
    Last edited: Feb 16, 2012
  12. Feb 16, 2012 #11
    This is really confusing, spacetime is malable like an elastic, and is constantly changing, evolving, and effects on it are caused by massive objects, which is a consequence of gravity on spacetime. Not malable in the sense that you can grab it in your hands, but it is malable by objects sitting in it.

    Can you elaborate a little further on what you mean by this?
  13. Feb 16, 2012 #12
    In some circumstances (which includes most everyday and most classical settings, like for example solar system orbital physics), but not always, we can get a good approximation (and do useful physics calculations or mental visualisations) even if we separate space from time. In those case, we can see space evolving in time, we can see how the presence of a mass deforms space, how a moving mass would cause a moving deformation of space, how masses moves according to those deformations, how deformations of space will varie over time. In those cases you are right, we can see space (not spacetime) as something malleable.

    But when you consider space and time bundle together into spacetime, you get a definitive and complete structure.
    You get the whole universe over all space and time. It is not a function of space or time anymore.
    If we (try to) isolate space from time, then we may wonder if space is expanding, etc.. But if we consider spacetime, it is not expanding.

    In a similar way, a movie doesn't change, it is the movie that it is, nothing less, nothing more.
    Of course someone watching a movie image by image might see the image change and the story evolve, but the movie as a whole doesn't.
    Last edited: Feb 16, 2012
  14. Feb 16, 2012 #13
    That's all pretty philosophicarhetorical thar...

    Can you explain this picture then?

    http://icanhascheezburger.files.wordpress.com/2009/07/funny-pictures-cat-barely-fits-in-box.jpg [Broken]

    Sorry, alot of what you just said didn't make much sense. I mean it does if you extrapolate it into philosophical terms, but it doesn't really describe spacetime in the classic sense of physics. I guess if your 5th dimensional everything looks like a big blob. >.>
    Last edited by a moderator: May 5, 2017
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