Invariance properties of the Dirac monopole

The quantum mechanical motion of a spinless electron in the external field of a magnetic monopole of magnetic charge μ is investigated. It is shown that Dirac's quantum condition $\text{2μe(}\text{h}\text{?}\text{c)}{}^{\mathrm{?1}}\text{= n}$ for the string being unobservable ensures rotation invariance and correct space reflection properties for any integer value of n. The rotation and space reflection operators are found and their group theoretical properties are discussed. When n is odd, half-integer j representations of the SU(2) group emerge without the introduction of spin. A method for constructing conserved quantities in the case when the potential is not explicitly invariant under the symmetry operation is also presented and applied to the discussion of the angular momentum of the electron-monopole system.     

Skeletal muscle lymphoma: MRI evaluation.

The magnetic resonance imaging (MRI) features of two cases of malignant lymphoproliferative disease involving skeletal muscle are presented. In both cases involved muscles were quantitatively and subjectively hypointense to fat on T1-weighted spin echo images, hypointense or isointense on T2-weighted spin echo images, and hyperintense on short tau inversion recovery (STIR) images. The findings suggest that lymphoproliferative disease should be considered as an etiology of a skeletal muscle lesion that is hypointense or isointense to fat on T2-weighted spin echo magnetic resonance images.     

Quantum affine algebras and deformations of the Virasoro and 237-1237-1237-1

Using the Wakimoto realization of quantum affine algebras we define new Poisson algebras, which areq-deformations of the classicalW. We also define their free field realizations, i.e. homomorphisms into some Heisenberg-Poisson algebras. The formulas for these homomorphisms coincide with formulas for spectra of transfer-matrices in the corresponding quantum integrable models derived by the Bethe-Ansatz method.Partially supported by NSF grants DMS-9205303 and DMS-9296120.     

Untersuchung der Kinetik der Sorption der Lösungsmitteldämpfe durch Ionomere auf der Basis des Copolymerisats von Styrol und Acrylsäure

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