# Nondemolition principle of quantum measurement theory

@article{Belavkin1994NondemolitionPO, title={Nondemolition principle of quantum measurement theory}, author={Viacheslav P. Belavkin}, journal={Foundations of Physics}, year={1994}, volume={24}, pages={685-714} }

We give an explicit axiomatic formulation of the quantum measurement theory which is free of the projection postulate. It is based on the generalized nondemolition principle applicable also to the unsharp, continuous-spectrum and continuous-in-time observations. The “collapsed state-vector” after the “objectification” is simply treated as a random vector of the a posterioristate given by the quantum filtering, i.e., the conditioning of the a prioriinduced state on the corresponding reduced…

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