Effect of long-range spreading on two-species reaction-diffusion system

Šarlota Birnšteinová

Stochastic models describe wide class of problems such as reaction-diffusion processes, nonequilibrium phase transitions, turbulent flows and others. Common feature of these models is a presence of strong fluctuations, which cause failure of ordinary perturbation theory. Main aim of this work is to study two-species reaction system A+B → 0 and A+A → (0,A) in presence of long-range spreading described by Lévy flights and to analyze the large-scale behavior of the model near its critical dimension using field-theoretic approach and renormalization group method.

Renormalization group investigation of phase transitions in static and dynamic models with different symmetry

Grigorii Kalagov

The purpose of the present work is to study the scaling phenomena and phase transitions in many-particle classical and quantum systems (turbulence, color superfluidity etc.) within the methods of quantum field theory. The technical methods we use and develop are expected to be applied to the problem of phase transitions in higher energy physics and physics of cold atoms. We will discuss some results of our investigation.