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Can Physics Explain Physics?

  1. Jan 19, 2005 #1
    This question might better be worded as such:

    Can physics explain the existence of physics?

    Please feel free to have a go at this one!
  2. jcsd
  3. Jan 19, 2005 #2
    For clarification, since it is a bit of a snake biting its butt question, let me try to confuse you further.

    Can we use physics to explain the existence of physics or must we step outside of the confines of that study and observe physics as the result of some other phenomenon (or massive study we don't know anything about)?
  4. Jan 19, 2005 #3


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    I'm sure people will cite godels theorem here and and use this to say something about the limits of physics. However, I think such an argument would be misguided. Of course we can't use any tool to prove anyting about the real world. For all we know, every event has been random, and it is just an unbelievably amazing coincidence that regularity is observed. That being said, it is still possible that the final laws of physics will be so compelling that we will look at them and decide they couldn't have been any other way. But the question of why there are laws or a universe at all will always remain unanswerable.
  5. Jan 19, 2005 #4
    I didn't find your question confusing.

    I don't use physics to explain anything. Therefore, you can bet I don't use it to explain itself.
  6. Jan 19, 2005 #5


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    Physics is the study of the observed universe, it is not the study of why the universe exists, or why there is something to observe. Why questions are outside of the realm of Physics. So the answer to your question is trivail, No.
  7. Jan 19, 2005 #6


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    I basically agree with Integral, but maybe you can elaborate on the meaning of your question. For instance, "the existence of physics" may mean the existence of the formal discipline that we call 'physics', or you may have had in mind the existence of the *laws* of phyics (or the basic symmetries, if you wish). It can also refer to the actual objects that physics studies.

    Which one is it?
  8. Jan 19, 2005 #7


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    At least for now they are
  9. Jan 19, 2005 #8


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    Would it be more precise to say that 'why' questions, to this point in the advancement of physics, always bottom out with some 'why' question that cannot (yet) be answered? For instance, one could ask the question "Why does this particular nuclear decay not occur?" and somebody might be able to answer it by showing that it would be a strong nuclear interaction that would violate parity conservation. But then the questioner asks, "Why do strong interactions conserve parity?" and so on, and at some point the other person is going to run out of answers.
  10. Jan 20, 2005 #9
    After posting this question I did think about revising it to ask

    "why do the laws of physics exist, can physics answer that question"

    Physics answers billions of "why" questions. Why is the sky blue? (the answer being one of many physical laws to do with optics and light refraction etc...)

    I'd say the laws exist so that we can observe them. The laws of physics make it possible, in more ways than one, to observe the laws of physics. But that is an esoteric answer... there may be less "whoo whoo" answers.
  11. Jan 20, 2005 #10


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    I don't agree that the laws of physics exist so we can observe them. That is almost saying that a creative intelligence designed these laws just for us. Perhaps there is no reason that the laws of physics can be observed, but as humanity has taken advantage of learning about the description of our environment, we have been able to see the laws much more clearly.
  12. Jan 20, 2005 #11
    What I think Integral meant is what I clarified in a long-since-forgotten thread: Physics doesn't answer "what purpose" questions, but it can answer "what cause", and both "what purpose" and "what cause" are translatable as "why" questions. IOW, Physics does answer "why" questions, but not of the "what purpose" brand (or, AFAIK, of any other brand...other than "what cause").

    So, to ask "why do the laws of physics exist" is to as "for what purpose do the laws of physics exist", and it is thus outside of physics. "Why is the sky blue" (which is actually "why does the sky appear blue to me" or "why can it be said, without fear of debate, that the sky is blue"), OTOH, is the same as "what causes the sky to be blue" (or "what causes me to perceive the sky as blue").
  13. Jan 20, 2005 #12
    I hate to nit-pick, but I'm pretty sure that Integral was referring to the impossibility in principle of physics' ever answering a why ("what purpose") question. I wouldn't have contradicted you, it's just that I think that's the integral point (forgive the pun) of this particular thread.
  14. Jan 20, 2005 #13


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    I think physics eventually does answer those "what purpose" and "why questions", especially when we become more knowledgeable. As for Integral's reference of "why the universe exists, or why there is something to observe", our current understanding of physics cannot answer this, I agree of course. Since we do not have the absolute answers to these questions, closing the door on the possiblity that physics can answer this sort of why question could limit our range of understanding. :smile:
  15. Jan 20, 2005 #14
    Well, we (humans) could eventually find all of those answers, but (IMHO) not via physics. Physics is designed a certain way, to answer certain kinds of questions. It'd be like trying to use a screwdriver as a level: it's just not what it's made for.
  16. Jan 20, 2005 #15
    we humans have worked so hard to complicate things, and now we have to work much harder to simplify things.
  17. Jan 20, 2005 #16
    These are great pointers and answers to this question. Thank you for all this.

    "Why questions" or, "what purpose is this" questions are relative. Relativity is a part of physics. Therefore the concept of "purpose" is a part of and perhaps an integral part of physical laws. For instance there is a purpose tied to every cause. For instance the physical law/function of osmosis is initiated by an imbalance and inequity in a fluid's chemistries and osmosis acts, purposefully and effectively, to correct the imbalance.
    The Why question here is cyclical and the only way to break the cycle is to ask why chemicals and fluids exist in the first place.

    This is a similar dilema to the question I have asked. So, I do confer to those people claiming the question to be futile and the answer even more elusive. But, I have found that it is possible to apply a law from physics to explain the existance of the laws of physics.

    We can agree that there is perhaps a state where physical laws do not apply. One that we could perhaps not fathom since we are physical beings. In the interest of the symmetry of the laws of balance this non-physical state may demand that there be laws of physics as its counter weight, if you will. Just as matter has an anti-matter counterpart and something requires (the space that) nothing (creates) to exist.
  18. Jan 21, 2005 #17
    But supposing 'Physics' turns around and says to you:

    The problem is not about me explaining myself because I am physics (already self-explained). I am eveything fully reduced to myself. The problem is in you, the outsider, trying to explain me or reduce everything to me. The problem of explanation or reductrion is yours and not mine.

    What would be your response to that?
  19. Jan 21, 2005 #18
    In predicate calculus, 'Physics' could even quantificationally declare:

    'Take anything, if it as the property of being something is me'

    How would you respond, knowing fully well that this also includes you?
  20. Jan 21, 2005 #19
    Personally, I'd say to "physics" (using physical laws to communicate with physics) exactly what I'd say to a performer who has no audience:

    "Dear physics,

    you are nothing with out me because 'if there ain't no audience, there ain't no show'." (Dr. B. Henderson)

    This, to a degree, explains why I first suggested that physics exists to observe itself through its own refinement of its own elements which has, thus far, resulted in the curious and inquisitive mind of the human and/or similar physical being.
  21. Jan 21, 2005 #20


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    Physics is used to explain our brains.

    Our brains created physics as we know it.

    Thus ...
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