On the problem of a local extension of the quantum formalism

The suggested impossibility of a consistent local extension of the quantum formalism is reviewed in the context of the Einstein–Podolsky–Rosen–Bohm (EPRB) ideal experiment. A consistent local theory Th(G) extending the quantum formalism is proposed. The postulates of Th(G) stipulate a finer state specification than that given by the quantum state ‖γ1,γ2≳. This describes how the spontaneous annihilation process itself breaks the spherical symmetry of the singlet state ‖γ1,γ2≳ into a pair of back‐to‐back photons having only axial symmetry about the direction of their motion. The theory Th(G) shows that local action suffices to explain all that the quantum formalism predicts for the EPRB ideal experiment as well as some other results.