Effects of new physics to the the ρ\rho--parameter in the supersymmetric standard model

The contribution to the $\rho$--parameter of the quark--Higgs sector of the supersymmetric standard model is computed non--perturbatively using the large--\nf expansion for the case tan$\beta$=0. An explicit formula is found for the $\rho$--parameter which is ill-defined unless the triviality cutoff is taken into account. The cutoff dependence of the $\rho$--parameter is found to be large if and only if the top mass is larger than $2v$ so that the cutoff scale is of the order of the electroweak scale. These non--universal effects are the reflections at low energies of the physics beyond the supersymmetric standard model. By also considering the effects of the soft--breaking terms, cutoff effects in both decoupling and non--decoupling effects are analyzed.Comment: 12 pages (5 figs), TIT/HEP-233, harvma

Some thermal transport properties of the FPU model with quadratic pinning

Thermal transport properties of the FPU $\beta$ model with a quadratic pinning term are investigated for various couplings and temperatures. In particular, the size dependence of the thermal conductivity, $\kappa\propto L^\alpha$, is studied. $\alpha$ agrees with that of the FPU $\beta$ model (with no pinning) at high temperatures but decreases at low temperatures. This crossover behavior occurs at a temperature depending on the strength of the quadratic pinning.Comment: 10pages, 4 fig