Upscaling Polymer Flooding in Heterogeneous Reservoirs

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Difficulty in the Fermi-Liquid-Based Theory for the In-Plane Magnetic Anisotropy in Untwinned High-T_c Superconductor

Recently, Eremin and Manske [1] presented a oneband Fermi-liquid theory for the in-plane magnetic anisotropy in untwinned high-Tc superconductor YBa2Cu3O6:85 (YBCO). They claimed that they found good agreement with inelastic neutron scattering (INS) spectra. In this Comment, we point out that their conclusion on this important problem may be questionable due to an error in logic about the orthorhombicity delta_0 characterizing the lattice structure of YBCO. In Ref. [1], a single band at delta_0>0 is proved to be in accordance with the angle resolved photoemission spectroscopy (ARPES) on untwinned YBCO. But in their Erratum in PRL[3], they admit that delta_0= -0.03 was used to fit the INS data. Hence publications [1,3] contain errors that we believe invalidate their approach.Comment: This is a Comment on the paper of I. Eremin, and D. Manske, Phys. Rev. Lett. 94, 067006(2005

Power-law behavior and condensation phenomena in disordered urn models

We investigate equilibrium statistical properties of urn models with disorder. Two urn models are proposed; one belongs to the Ehrenfest class, and the other corresponds to the Monkey class. These models are introduced from the view point of the power-law behavior and randomness; it is clarified that quenched random parameters play an important role in generating power-law behavior. We evaluate the occupation probability $P(k)$ with which an urn has $k$ balls by using the concept of statistical physics of disordered systems. In the disordered urn model belonging to the Monkey class, we find that above critical density $\rho_\mathrm{c}$ for a given temperature, condensation phenomenon occurs and the occupation probability changes its scaling behavior from an exponential-law to a heavy tailed power-law in large $k$ regime. We also discuss an interpretation of our results for explaining of macro-economy, in particular, emergence of wealth differentials.Comment: 16pages, 9figures, using iopart.cls, 2 new figures were adde