Numerical modeling of the multi-stage Stern$\text{unicode}x2013$Gerlach experiment by Frisch and Segrè using co-quantum dynamics via the Schrödinger equation

We use a theory termed co-quantum dynamics (CQD) to numerically model spin flip in the multi-stage Stern$\text{unicode}x2013$Gerlach (SG) experiment conducted by R. Frisch and E. Segrè. This experiment consists of two Stern$\text{unicode}x2013$Gerlach apparatuses separated by an inner rotation chamber that varies the fraction of spin flip. To this day, quantum mechanical treatments inadequately predict the Frisch$\text{unicode}x2013$Segrè experiment. Here, we account for electron-nuclear interactions according to CQD and solve the associated Schrödinger equation. Our simulation outcome agrees with the Frisch$\text{unicode}x2013$Segrè experimental observation and supports CQD as a potential model for electron spin evolution and collapse.