Observing a changing Hilbert-space inner product

  title={Observing a changing Hilbert-space inner product},
  author={Salini Karuvade and Abhijeet Alase and Barry C. Sanders},
  journal={Physical Review Research},
In quantum mechanics, physical states are represented by rays in Hilbert space H , which is a vector space imbued by an inner product 〈 | 〉, whose physical meaning arises as the overlap 〈φ|ψ〉 for |ψ〉 a pure state (description of preparation) and 〈φ| a projective measurement. However, current quantum theory does not formally address the consequences of a changing inner product during the interval between preparation and measurement. We establish a theoretical framework for such a changing inner… 

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