RPA response function for quasielastic electron scattering in the relativistic σ-ω model

In the Hartree approximation for the relativistic σ-ω model, the σ-meson dominates the longitudinal response function for quasielastic electron scattering, through the effective mass of the nucleon. In the random phase approximation, however, the effective mass effect is cancelled by the particle-hole correlation due to the σ-meson exchange, and the ω-meson also plays an important role in the response function.     

Absence of spontaneous magnetization in spin systems with competing interactions

It is rigorously proved that spontaneous magnetization is absent in disordered spin systems if the strength of interaction is distributed symmetrically around a vanishing mean value, as a consequence of local gauge symmetry. This result is extended also to asymmetric distributions. A comment is made on gauge symmetry and frustration in quantum spin systems.     

Double affine Hecke algebras,conformal coinvariants and Kostka polynomials

We study a class of representations called ‘calibrated representations’ of the rational and trigonometric double affine Hecke algebras of type ${\mathit{GL}}_n$. We give a realization of calibrated irreducible modules as spaces of coinvariants constructed from integrable modules over the affine Lie algebra ${\stackrel{?}{\mathfrak{gl}}}_m$. We also give a character formula of these irreducible modules in terms of a generalization of Kostka polynomials. These results are conjectured by Arakawa, Suzuki and Tsuchiya based on the conformal field theory. The proofs using recent results on the representation theory of the double affine Hecke algebras will be presented in the forthcoming papers. To cite this article: T. Suzuki, C. R. Acad. Sci. Paris, Ser. I 343 (2006).     

Possible observation of the quadrupolar Kondo effect in dilute quadrupolar system Pr(x)La(1-x)Pb3 for x <or= 0.05

We have studied non-Fermi-liquid (NFL) behavior in Pr(x)La(1-x)Pb3 with Gamma3 quadrupolar moments in the crystalline-electric-field ground state. The specific heat C/T shows NFL behavior in the very dilute region for x 相似文献