THE GEOMETRY OF QUANTUM STATES

0f = 2 [°0 4 V/(ao2 + 4Q2A2)]. (43) 2 * The research reported in this paper has in part been supported by the Geophysics Research Directorate of the Air Force Cambridge Research Center, Air Research and Development Command, under Contract AF 19(604)-2046 with the University of Chicago. I Chandrasekhar, S., "The Stability of Viscous Flow Between Rotating Cylinders in the Presence of a Magnetic Field," Proc. Roy. Soc. (London), A216 293-309 (1953); also, Niblett, E. R., "The Stability of Couette Flow in an Axial Magnetic Field," Canadian J. Phys., 36, 1509-1525 (1958). These papers deal with the case of two cylinders rotated in the same direction; the case when they rotate in opposite directions has recently been investigated and will be published in due course. 2 Velikhov, E. P., "Stability of an Ideally Conducting Liquid Flowing Between Cylinders Rotating in a Magnetic Field," J. Exptl. Theoret. Phys. (U.S.S.R.), 36, 1398-1404 (1959). 3 For the significance of this discriminant see Chandrasekhar, S., "The Hydrodynamic Stability of Inviscid Flow Between Coaxial Cylinders," these PROCEEDINGS, 46, 137 (1960). 4 I am grateful to Dr. H. W. Reid for communicating to me his unpublished results.