Fig. 7.6 On the left [right]: supercritical [subcritical] pitchfork bifurcation, Eq. (7.69) [Eq. (7.70)],
for l ¼ À1; 0; þ 1. Colour conventions are the same as in Fig. 7.4. The magnetic symmetry is
given by Eq. (7.74)
7 Topology of Quantum Mechanical Current Density …
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