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Laws of the universe

  1. Aug 14, 2006 #1
    There are certain laws that govern this universe of ours. for example - the universal law of gravitation, the maxwell's laws and in case it does exist, the TOE... Now consider a universe as a set of laws. So if we give any random set of laws, it uniquely defines a universe. There can of course be some constraints on the set of laws in order to make it define a possible universe, for example, one of the constraints might well be that none of the laws in the set should contradict another. Once we define a universe in this way, we can start imagining various kinds of bizarre universes with several unimaginable laws. And this exercise raises an interesting question. Is there a law that MUST be true in all kind of universes? And if you think on this question for a while, you might come up with the following law :-

    Consider an object which is very rigorously defined, for example, may be, a red ball (a red ball might not be rigorously definable, but that's not the issue here... let's just assume that it is). So then in a given universe, a red ball either exists or doesn't exist.

    Now let's analyse this law. Of course, in our universe, it is true... a red ball either exists or doesnt...

    But is it necessarily going to be true in all the conceivable universes?

    I mean, are logical statements like this bound to be true in ALL the universes we can possibly imagine?
     
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  3. Aug 14, 2006 #2

    selfAdjoint

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    Hurkyl noted, up on the Relativity board, that among all relativistic universes, the existence of a spin structure (which we observe) requiires the vanishing of a topological invariant, the first Stiefel-Whitney class. Thus the topology of all possible universes that are like what we observe is somewhat constricted.

    Theorists do think the way you do when they imagine things like "theory space", which some of therir tools, like the renormalization group, require them to do.
     
  4. Aug 14, 2006 #3

    Office_Shredder

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    The first question that popped up into my mind:

    If there is a constraint that no universe can have contradictory laws, then wouldn't a set of laws that permits a red ball to either exist or not exist be contradictory by our logic?

    Then whose logic are we using to determine whether a set of laws is contradictory?
     
  5. Aug 14, 2006 #4

    selfAdjoint

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    The excluded middle is not followed by quantum mechanics, which is I think an "observed constraint" for any universe that contains us.
     
  6. Aug 16, 2006 #5


    I don t know how you can imagine different universes. Laws are mysteries things, like software engineering, and woman. It is used to perdict, but why laws are they way are is something i do not know. my points is: the universe is more than a set of consistent statements.


    let me get your point streigh. can an apple exist, and not exist at the same time in a system where there is no contradiction between facts( whatever). my answer is no, because you made your universe so by your formulation.
     
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