Nonunitary transformation, nonintegrable

The situation changes drastically for nonintegrable systems. As we will see, the transformation U = U is replaced by a nonunitary transformation At A. ... 

Classical dynamics and orthodox quantum mechanics are constructed along the model of integrable systems in the sense of Poincare. Our aim is to construct dynamics for nonintegrable systems. As far as we know, this is a new attempt, which has its roots in the early work of the Brussels School [1-9]. The main result is that we have to replace the unitary transformation f/ by a nonunitary... 

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