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Critical dynamics in systems controlled by fractional kinetic equations

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 نشر من قبل Batalov Lev
 تاريخ النشر 2012
  مجال البحث فيزياء
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The article is devoted to the dynamics of systems with an anomalous scaling near a critical point. The fractional stochastic equation of a Lanvevin type with the $varphi^3$ nonlinearity is considered. By analogy with the model A the field theoretic model is built, and its propagators are calculated. The nonlocality of the new action functional in the coordinate representation is caused by the involving of the fractional spatial derivative. It is proved that the new model is multiplicatively renormalizable, the Gell-Man-Low function in the one-loop approximation is evaluted. The existence of the scaling behavior in the framework of the $varepsilon$-expansion for a superdiffusion is established.



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