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Self Reference and Physics

  1. Nov 11, 2009 #1
    Is there self reference in Nature?

    Foundations of The Quantum Logic
     
  2. jcsd
  3. Nov 19, 2009 #2
    are you refering to how particles, in the quantum mechanics realm, will always face the in the direction that you look at them? like the spin and such? because that only happens at those extremely small levels, and even those properties are unexplained even at the quantum level
     
  4. Nov 20, 2009 #3
    Self reference is a phrase used in logic. If I write a statement like: "The Universe includes the Physical Laws" and then write another: "The Physical Laws control the Universe", The two statements together imply that the Physical Laws control the Physical Laws. Which is self referent.
     
  5. Nov 20, 2009 #4

    A.T.

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    You can make arguments like this about anything:

    A robot is controlled by a computer & The computer is part of the robot. -> The computer controls the computer.

    Physical laws are not controlling anything but only describing a part of the universe. The physical laws themselves are not included in that part.
     
  6. Nov 20, 2009 #5
    ha ha, i was way off. And yes that makes sense but i dont think that physical laws control the universe. Its not like they have a mind of their own and can change when they want. They simply describe the actions of the universe.
     
  7. Nov 20, 2009 #6
    If the Physical Laws are not part of the Universe, where are they? If science is concerned with understanding the Physical Laws; is it not inconsistent, to accept without understanding, Agencies causing the Physical Laws?
     
  8. Nov 20, 2009 #7
    Yes you can make arguments like this about many things. Your own statement about computers is a good example of self reference. Do you know of a computer/robot, that is genuinely turned off, with no power to it, that can switch itself on?

    My question is whether a universe needs an outside agency to initiate it or can it do this by some self referent means. Although the question I am asking seems like some clever logical trick, that does not mean it should be disregarded. It is a proposition that can be addressed or alternatively ignored, but it cannot be dismissed on the grounds of not having a simple answer.
     
  9. Nov 20, 2009 #8

    A.T.

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    I didn't say that. I said physical laws are not included in the part of the universe, which is described by physical laws.

    Physical laws are human made quantitative descriptions of the observed nature. As long as no "agencies causing them" are observed in a quantitative manner, these "agencies" are not part of physics.

    I think your 'logical trick' is called "naive set theory" and was shown self-contradictory long ago:
    http://en.wikipedia.org/wiki/Russell's_paradox
     
    Last edited: Nov 20, 2009
  10. Nov 20, 2009 #9
    Russel's Paradox is not something to be brushed off lightly. It is related to The Liar Paradox: "This sentence is a lie." Kurt Gödel altered this slightly to "Is this sentence provable?" And from that question he proved his famous Incompleteness Theorems using self reference. Since that time Karl Svozil showed that physics is incomplete in this sense. [Svozil, K. (2005) undecidability everywhere? Institut fur Theoreische Physik, University of Technology, Vienna.]
    He uses Turing's proof. My question, by extension is: is there self Reference in Nature? I suspect there is and I suggest we look for it.
     
  11. Nov 21, 2009 #10

    A.T.

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    I'm not brushing it off. It shows that playing logical games with self referencing sets leads to contradiction. So why bother with it?
    Fortunately physics can live quite well with incompleteness. It is a problem of math, logic and philosophy.
     
  12. Nov 21, 2009 #11
    On the grounds of scientific open-mindedness should we not look at logic for answers in physics? Quantum Physics has logical problems. Issues have gone without answer for at least 83 years. So too does Chaos.

    A recent line of enquiry:

    Foundations of The Quantum Logic
    http://steviefaulkner.wordpress.com/
     
  13. Nov 21, 2009 #12
    For me the biggest self-reference is the brain trying to analyse/comprehend itself and its perceptions. Philosophically, I see it as a dead-end.
     
  14. Nov 21, 2009 #13

    apeiron

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    Ising models seem like a good example of bootstrapping logic. The dipoles line up to make the magnetic field and the magnetic field bears down to line up the dipoles.

    And we would then extrapolate this self-organising phase transition logic to the universe. So the local events line up to make the global laws and the global laws bear down to line up the local elements.

    Self-reference occurs in paradoxical fashion when it is considered at just a single scale. As with the liar's paradox. But if scale is dichotomised, then paradox disappears.

    So it seems paradoxical to talk of the universe and its laws as causing each other. That is just a circular loop with no causal content.

    But then we realise that the universe is actually composed of the small and the large, the local events and its global laws. We were making a mistake in thinking of the universe as the global scale. In fact it is a term for all scales. And now we can see that what we really want to talk about are the two extremes of scale that compose the system we call the universe.

    Once we ask the question in terms of local events and global laws - which constitutes the universe? well they both do in equilibrium interaction across all scales - then this self-referential logic becomes non-paradoxical.
     
  15. Nov 21, 2009 #14

    A.T.

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    No. The answers in physics come from experiments. Physics uses some concepts of math and logic, but not everything. The obsession with completeness for example is useless to physics, and didn't even work out for math itself.
     
  16. Nov 21, 2009 #15

    apeiron

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    We are witnessing this again with quantum gravity of course. This is exactly an issue of self-reference where we want to reduce the container to its contents, the continuous to the discrete. So knowing how to deal with completeness remains a live research question.
     
  17. Nov 22, 2009 #16
    How the Universe works does not involve experiments nor our understanding it. It proceeds without us according to whatever symmetry rules are in it, as well as whatever rules of logic govern cause and effect. If physics concerns only experiments and people, then I am not talking about physics; I am talking about Nature.

    My original question was:
    I'll try and make the distinction more clearly from now.


    Foundations of The Quantum Logic
     
  18. Nov 22, 2009 #17
  19. Nov 22, 2009 #18
    in our heads.
    there are no physical laws "out there"... they're just descriptive models we devised so that we may easily understand the universe and the physical processes.

    as for the main inquiry of the OP- are there self-referential systems? well, if we rephrase that to "are there systems capable of self-referential processes?" then the answer is an obvious yes: human beings and any self-aware animal.
     
  20. Nov 22, 2009 #19
    I think I can agree to this; I think.


    When I say Physical Laws, I am not talking about the things we write down on paper; I am talking about those things in Nature that govern the physical processes. They might be a system of symmetries.

    I can see I need to word my questions much more carefully.

    Foundations of The Quantum Logic
     
  21. Nov 22, 2009 #20

    apeiron

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    Hmm. I think the clue you are missing here is that undecideability is a result of symmetry. So paradoxes emerge in logical arguments, for example, when the force of the argument seems to go equally in both directions. We get this kind of self-referential circularity that we see in the liar's paradox because there is no scale that makes one part of the argument event, the other context.

    Singularities are another example of a symmetry state which are therefore indeterminate. Same with wavefunctions.

    So what you should really be focusing on is the process of symmetry and symmetry breaking - the creation of scale.

    We "know" that our universe originated from a state of quantum symmetry, a planckscale singularity. Well, that is the best current model. We also know that there were a cascade of further symmetry breakings in which the forces cracked out. So the task really seems to be to imagine what state could be even more symmetrical than the big bang singularity. Which is where people are exploring E8 and the zoo of higher symmetries.

    Anyway, what has caught your attention is undecidability in logic. The reasons this happens is that, at its limits, logic loses its necessary asymmetry - its arrow of causality - and becomes symmetrical. This can be related to lie algebra (the loss of mathematical structure with increasing dimension), to quantum indeterminancy, and to the philosophical notion of vagueness. So it is a symptom rather than a cause.
     
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