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Deterministic Universe (3 propositions)

  1. Mar 24, 2010 #1
    1 - Can we argue that the wave function is used to determine all possible temporary states of a quantum system, and that via Schrodinger’s equation evolving deterministically the quantum system influences and is influenced by the Universe in a deterministic way? If the Universe has its own wave function, then too can we say it unfolds in a deterministic manner if it can not be broken down into subsystems?

    2 - Or, can we argue that if a quantum system is in a superposition of states, and it is only a mathematical description, then it may not be influenced or have any influence over the physical Universe when the quantum particle is in its quantum state? With decoherence at work, it becomes a part of the determined in principle macro scale. This would mean prior to the interaction with the environment, the Universe would default to influencing and being influenced by existing properties and variables that are real in the physical Universe.

    3 - Or, can we say that unique point particles of micro events (hidden variables) do influence and are influenced by the physical Universe, simply because this would equate to realism within the particle.

    It seems these three options argue for a deterministic Universe. What other options are available? Either quantum systems influence and are influenced by the natural physical world deterministically via Schrodinger’s wave, or they are in a superposition of states with no influences as they do not technically exist and the way the Universe develops is due to only existing variables, or they exist as actual point particles. All of these propositions argue for a deterministic model of what influences and is influenced by the Universe. I am not sure where true randomness inserts itself. If we say randomness is evident, then it must do so in the collapse/decoherence part of the process.

    Am I reaching here, what do you think?
  2. jcsd
  3. Mar 24, 2010 #2
    I think that you are correct. Everything seems to evolve deterministically except for the collapse/decohering of a wavefunction. Although, given the latter point, we can't conclude one way or another, I don't think. Also, what of the uncertainty principle. When the unobserved variable becomes uncertain (e.g. momentum when position is observed), do we state that momentum ceases to evolve deterministically? I'd really like a physicists perspcetive though.

    See the related thread in the QM section:
    Last edited: Mar 24, 2010
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