Документы

  • universe-08-00072

    Конечная издательская версия, 393 KB, Документ PDF

DOI

We study the stochastic Kardar-Parisi-Zhang equation for kinetic roughening where the time-independent (columnar or spatially quenched) Gaussian random noise f (t, x) is specified by the pair correlation function 〈 f (t, x) f (t , x )〉 ∝ δ (d) (x − x ), d being the dimension of space. The field-theoretic renormalization group analysis shows that the effect of turbulent motion of the environment (modelled by the coupling with the velocity field described by the Kazantsev-Kraichnan statistical ensemble for an incompressible fluid) gives rise to a new nonlinear term, quadratic in the velocity field. It turns out that this “induced” nonlinearity strongly affects the scaling behaviour in several universality classes (types of long-time, large-scale asymptotic regimes) even when the turbulent advection appears irrelevant in itself. Practical calculation of the critical exponents (that determine the universality classes) is performed to the first order of the double expansion in ε = 4 − d and the velocity exponent ξ (one-loop approximation). As is the case with most “descendants” of the Kardar-Parisi-Zhang model, some relevant fixed points of the renormalization group equations lie in “forbidden zones”, i.e., in those corresponding to negative kinetic coefficients or complex couplings. This persistent phenomenon in stochastic non-equilibrium models requires careful and inventive physical interpretation.

Язык оригиналаанглийский
Номер статьи72
Число страниц16
ЖурналUniverse
Том8
Номер выпуска2
DOI
СостояниеОпубликовано - 26 янв 2022

    Предметные области Scopus

  • Физика и астрономия (все)

ID: 92115752