Journal of Physics A Mathematical and General
Critical behaviour of the long-range ( ϕ2)2model in the short-range limit
Juha Honkonen
Abstract
The relation between scaling regimes described by ( ϕ 2 ) 2 field theories with long-range and short-range exchange is analysed. It is shown that the crossover from the long-range regime to the short-range regime takes place due to the singular behaviour of three-loop and higher-order contributions to the beta function of the renormalization group, which controls the scaling behaviour of the long-range model. The critical exponents eta and nu are shown to be continuous functions of the parameter alpha , which characterises the power-like fall-off of the exchange interaction.