Replica field theory for the Ising spin glass in zero magnetic field is studied around the upper critical dimension d=6. A scaling theory of the spin glass phase, based on Parisi’s ultrametrically organised order parameter, is proposed. We argue that this infinite step replica symmetry broken...

We study the influence of an aperiodic extended surface perturbation on the surface critical behaviour of the two-dimensional Ising model in the extreme anisotropic limit. The perturbation decays as a power κ of the distance l from the free surface with an oscillating amplitude <InlineEquation ID="IEq1"> <EquationSource Format="TEX"> $A_l =( -...</equationsource></inlineequation>

We show that the numerical method based on the off-equilibrium fluctuation-dissipation relation does work and is very useful and powerful in the study of disordered systems which show a very slow dynamics. We have verified that it gives the right information in the known cases (diluted...

We consider polymers, modelled as self-avoiding chains, confined on a strip defined on the square lattice with spacing a in the (x,y) plane, limited by two walls which are impenetrable to the chains and located at x=0 and x=am. The activity of a monomer incorporated into the chain is defined as...

Thermostatic properties of Stanley's classical n-vector model on the harmonic chain are studied. It is shown that this model belongs to a rather general class of classical spin models in one dimension. The members of this class are characterized by spins which are elements of a homogenous space...