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  What's the physical meaning of the Invariant Set theory?

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I am reading about the Invariant Set (IS) theory, defined by its originator Tim Palmer as "a locally causal ontic theory of physics based on the Cosmological Invariant Set postulate that the universe U can be considered a deterministic dynamical system evolving precisely on a (suitably constructed) fractal dynamically invariant set in U’s state space."

Palmer says (my interpretation) that, in the global state space of the universe, some states are allowed and other states are not allowed, and the set of allowed states has a complex fractal geometrical structure that could permit making senses of the weirdness of quantum physics. So for example a state of the universe where the spins of two entangled particles are measured in opposite directions is in the IS, and one in which they are measured in the same direction is not in the IS. But in general the IS is non-computable - there is no algorithmic shortcut to decide if a state of the universe is in the IS or not.

Palmer's papers have received good reviews, and seem interesting and well written - beginning with "Quantum Reality, Complex Numbers and the Meteorological Butterfly Effect," written before his Invariant Set articles.

However, at a first glance it seems to me that Palmer is saying "A can happen because it is in the set of physically possible states of the universe, and B can't happen because it is not in the set of physically possible states of the universe," which is just another way of saying "things happen because they do" and doesn't permit making predictions if the geometry of the IS set of possible states of the universe is universe is unknown and non-computable.

So I guess I am missing the physical meaning of Palmer's ideas and would appreciate clarifications.

asked Sep 28, 2015 in Theoretical Physics by Giulio Prisco (190 points) [ no revision ]

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