What is the most general and abstract statement of "quantization" in quantum mechanics?

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When I read physics explanations of "quantization", I am confused, because they talk about particles, momentum, and other specific things. It seems to me that quantum formalism is much more general than this (e.g. in quantum computing there are no "particles").

What is the most general statement of "quantization", i.e. "turning a classical model into a 'quantum version' of the same model"? i.e. what does quantization mean formally?

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Todorov's delightful article in the refs of your link emphasizes the arbitrary and non-unique version of such projects.

The proper definition is "turning a classical model into some quantum model whose classical limit is the classical model you started from". The procedure is heuristic and ill-defined, but, of course, in an overwhelming majority of cases addressed, the problem is rather straightforward to solve.

A classical model obeys Hamilton's differential equations to have its time-evolution specified, and this time evolution is summarized in classical trajectories.

A quantum model cannot have trajectories, but, instead describes how "states", vectors in a Hilbert space, evolve in time, through unitary evolution, i.e. acted upon by linear operators properly specified. Ultimately, suitable scalar products of such states, yield probabilities or expectation values of "observables" of use in physics, computing, etc... Physical systems involve a crucial "deformation parameter" $\hbar$, to connect to classical systems, but it is not crucial in purely formal discussions of QM.

Through the Weyl-Wigner invertible map, one may translate Hilbert space entities into phase-space ones (which is the ambit of Hamiltonian classical mechanics) so you may contrast a quantum model to the classical model resulting by taking a deformation parameter $\hbar\to 0$. As indicated, the quantum system contains much more information, in some sense, than its classical limit, which is then reachable from several different quantum models.