Recently, a morphological transition in the velocity distribution of a relativistic gas has been pointed out which shows hallmarks of a critical phenomenon. Here, we provide a general framework which allows for a thermodynamic approach to such a critical phenomenon. We therefore construct a...

The Ising model, in the presence of a random field, is investigated within the mean-field approximation based on Landau expansion. The random field is drawn from the bimodal probability distribution P(h)=pδ(h−h0)+(1−p)δ(h+h0), where the probability p assumes any value within the interval...

We study the phase diagram of the ferromagnetic q-state Potts model on the various three-dimensional lattices for integer and non-integer values of q1. Our approach is based on a thermodynamically self-consistent Ornstein–Zernike approximation for the two-point correlation functions. We...

Using Wang–Landau entropic sampling we study the Ising model in the framework of microcanonical ensemble (fixed magnetization). We are working for lattice size up to 1500×1500 in two dimensions and 100×100×100 in three dimensions. As we approach the coexistence curve from inside, varying...

The Ising model in the presence of a random field is investigated within the mean field approximation based on Landau expansion. The random field is drawn from the asymmetric and anisotropic bimodal probability distribution P(hi)=pδ(hi−h0)+qδ(hi+λ∗h0), where the site probabilities p,q...

A generalization of the pure site and pure bond percolation problems called site–bond percolation on a triangular lattice is studied. Motivated by considerations of cluster connectivity, two distinct schemes (denoted as S∩B and S∪B) for site–bond percolation are used. In S∩B (S∪B),...

We present results of theoretical study of quasielastic behavior of ferrofluid filling a thin flat gap, placed into perpendicular magnetic field. When the field exceeds a certain critical magnitude, magnetic particles form dense discrete domains, elongated along the field, and linking the gap...

We study the damage spreading phenomena in two different ways in an opinion dynamics model introduced recently. This kinetic exchange type model is characterized by a fraction q of negative interactions and shows the presence of an order–disorder transition at qc. In the traditional method,...

We study the effects of including a distribution of valuable or attractive sites in a two-dimensional lattice in self-organizing social hierarchies. Agents move aleatorily except in the case where an attractive site is located in their neighborhood. We find that the transition between an...

The Pirogov–Sinai theory of phase transitions is used to prove the existence of ordered molecular phases at low temperatures in statistical mechanical models for several types of molecular systems. A three-dimensional lattice gas containing two molecular mirror images (enantiomers) was proved...