Schrödinger's cat and the clock: lessons for quantum gravity

  title={Schr{\"o}dinger's cat and the clock: lessons for quantum gravity},
  author={Robert Oeckl},
  journal={Classical and Quantum Gravity},
  • R. Oeckl
  • Published 2 June 2003
  • Physics
  • Classical and Quantum Gravity
I review basic principles of the quantum mechanical measurement process in view of their implications for a quantum theory of general relativity. It turns out that a clock as an external classical device associated with the observer plays an essential role. This leads me to postulate a 'principle of the integrity of the observer'. It essentially requires the observer to be part of a classical domain connected throughout the measurement process. Mathematically this naturally leads to a… 
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