Quantum Theory as a Factualization of Classical Theory

Abstract

Quantum theories of physics are based on the physical fact of the existence of the universal quantum of action, symbolized by the Planck constant h. Classical theories of physics ignore this fact. According to Bohr (1949) they are idealizations which can be unambiguously applied only in the limit where all actions involved are large compared with the quantum. This state of affairs suggests that there are some natural relationships between the two types of theories. First of all, it suggests that quantum theory is a factualization of classical theory where the counterfactual idealizing assumptions are replaced by their factualizations. Secondly, one is led to ask whether classical theory can be inferred from quantum theory and some additional, obviously counterfactual, assumptions. In other words, is classical theory a reduction of quantum theory, or, to reverse it, is quantum theory a generalization of classical theory? If this would be the case one could then argue that classical theory is in a correspondence relation to quantum theory.