Critical behavior at edge singularities in one dimensional spin models

In ferromagnetic spin models above the critical temperature ($T > T_{cr}$) the partition function zeros accumulate at complex values of the magnetic field ($H_E$) with a universal behavior for the density of zeros \rho (H) \sim | H - H_E |^{\sg}. The critical exponent \sg is believed to be universal at each space dimension and it is related to the magnetic scaling exponent $y_h$ via \sg = (d-y_h)/y_h. In two dimensions we have y_h=12/5 (\sg = -1/6) while y_h=2 (\sg=-1/2) in $d=1$. For the one dimensional Blume-Capel and Blume-Emery-Griffiths models we show here, for different temperatures, that a new value y_h=3 (\sg =-2/3) can emerge if we have a triple degeneracy of the transfer matrix eigenvalues.Comment: to appear in Phys. Rev. E, 16 pages, 3 figure

Analytical r-mode solution with gravitational radiation reaction force

We present and discuss the analytical r-mode solution to the linearized hydrodynamic equations of a slowly rotating, Newtonian, barotropic, non-magnetized, perfect-fluid star in which the gravitational radiation reaction force is present.Comment: 3 pages, in Proceedings of the 5th International Workshop "New Worlds in Astroparticle Physics", Faro, Portugal, 8-10 January 200

Superfluid and Fermi liquid phases of Bose-Fermi mixtures in optical lattices

We describe interacting mixtures of ultracold bosonic and fermionic atoms in harmonically confined optical lattices. For a suitable choice of parameters we study the emergence of superfluid and Fermi liquid (non-insulating) regions out of Bose-Mott and Fermi-band insulators, due to finite Boson and Fermion hopping. We obtain the shell structure for the system and show that angular momentum can be transferred to the non-insulating regions from Laguerre-Gaussian beams, which combined with Bragg spectroscopy can reveal all superfluid and Fermi liquid shells.Comment: 4 pages, 2 figure