Fig. 7.5 On the left [right]: supercritical [subcritical] transcritical saddle-vortex bifurcation,
Eq. (7.67) [Eq. (7.68)], for l ¼ À1; 0; þ 1. Colour conventions are the same as in Fig. 7.4
7 Topology of Quantum Mechanical Current Density …
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