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Decoherence caused

  1. Apr 18, 2010 #1
    It seems decoherence can not explain the measurement problem, but I wonder why I rarely read about the interaction between a quantum system and the environment being causal as an interpretation. What about a causal interpretation for the process of decoherence? This avoids a true collapse, avoids dependence on an observer, and avoids any mysticism in the process of acausal/spontaneous outcomes.
  2. jcsd
  3. Apr 18, 2010 #2


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    This is the approach I too would favour. But does it really matter that much?

    The decoherence position is that there is no global collapse, the wavefunction just leaks away to mix with that of the environment in a way that becomes effectively classical in look. So in my terms, this is a standard, locally constructive or bottom-up, view of the causality.

    And as a formalism, as a model of reality, this may be all that is needed. It seems a pragmatic way of avoiding the philosophical issues of an actual wave function collapse.

    But I too would prefer a more complete story in which the top-down constraints exerted by a decohered environment is also modelled. And I would see the transactional interpretation (with its retrocausality) as being about this expanded view (which sees top-down causality acting from the future even - the lightcone or global spatiotemporal scale).

    The question becomes whether the "more realistic" wider view is necessary if the simpler bottom-up approach of "dissipating information with no collapse" does the job. What new predictions would a more complex model, including top-down causality bring here?

    I believe it would add more. But I waiting to see exactly what.
  4. Apr 21, 2010 #3
    I guess objectively it does not matter that much. But, I still finding it interesting thinking about these things. I have not read much of Cramer's theory. I picked up Schroedinger's Kittens (I think that is the name of his book) once, but did not get through it. Is his theory held in high regards? Have there been any advances in his theory?
  5. Apr 22, 2010 #4


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