Evolution without evolution and without ambiguities

  title={Evolution without evolution and without ambiguities},
  author={Chiara Marletto and Vlatko Vedral},
  journal={Physical Review D},
In quantum theory it is possible to explain time, and dynamics, in terms of entanglement. This is the timeless approach to time, which assumes that the universe is in a stationary state, where two noninteracting subsystems, the ``clock'' and the ``rest,'' are entangled. As a consequence, by choosing a suitable observable of the clock, the relative state of the rest of the universe evolves unitarily with respect to the variable labeling the clock observable's eigenstates, which is then… 
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    Compendium of Quantum Physics
  • 2009
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