Quantum systems often exhibit fundamental incapability to entertain vortex. The Meissner effect, a complete expulsion of the magnetic field (the electromagnetic vorticity), for instance, is taken to be the defining attribute of the superconducting state. Superfluidity is another, close-parallel example; fluid vorticity can reside only on topological defects with a limited (quantized) amount. Recent developments in the Bose-Einstein condensates produced by particle traps further emphasize this characteristic. We show that the challenge of imparting vorticity to a quantum fluid can be met through a nonlinear mechanism operating in a hot fluid corresponding to a thermally modified PauliSchrödinger spinor field. In a simple field-free model, we show that the thermal effect, represented by a nonlinear, non-Hermitian Hamiltonian, in conjunction with spin vorticity, leads to new interesting quantum states; a spiral solution is explicitly worked out.

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Absfracf-Institute of Industrial Science, University of Tokyo and the Hydrographic and Oceanographic Department, Japan Coast Guard have been jointly developing the seafloor geodetic observation network around Japan. The seafloor reference points have been distributed along the major trenches, such as the Japan trench and the Nankai trough. 16 seafloor geodetic reference points have been deployed until the end of 2003. We have visited the seafloor reference points repeatedly in order to make measurements. Although we reached certain level with. the already existing system, we come np with possible improvements of the system as we accumulate the experience of the Observations using the system. Trials to improve the system are always done in order to achieve a fully centimeter level geodesy on the seafloor.