arXiv subjects

Alexander A. Migdal

Publications and source records attributed to Alexander A. Migdal.

3 recordsLinked to original sources

arXiv1994

Edge Singularity in ``Induced QCD"

The behaviour of the master field in ``induced QCD" near the edge of its support is studied. An extended scaling domain, where the shape of the master field is a universal function, is found. This function is determined explicitly for the case of dimensions, close to one, and the $D-1$-expansion is constructed. The problem of the meson spectrum corresponding to this solution is analyzed. As a byproduct of these calculations, a new, explicit equation for the meson spectrum in ``induced QCD" with a general potential is derived.

hep-th↗

arXiv1993

Loop Equation and Area Law in Turbulence

This is the extended version of the preprint \ct{Loop}, based on the lectures given in Cargese Summer School and Chernogolovka Summer School in 93. The incompressible fluid dynamics is reformulated as dynamics of closed loops $C$ in coordinate space. We derive explicit functional equation for the pdf of the circulation $P_C(Γ)$ which allows the scaling solutions in inertial range of spatial scales. The pdf decays as exponential of some power of $ Γ^3/A^2 $ where $A$ is the minimal area inside the loop.

hep-th↗

arXiv1993

Loop Equation in Turbulence

The incompressible fluid dynamics is reformulated as dynamics of closed loops $C$ in coordinate space. This formulation allows to derive explicit functional equation for the generating functional $Ψ[C]$ in inertial range of spatial scales, which allows the scaling solutions. The requirement of finite energy dissipation rate leads then to the Kolmogorov index. We find an exact steady solution of the loop equation in inertial range of the loop sizes. The generating functional decreases as $\EXP{-A^{\tt}}$ where $A=\oint_C r \wedge dr$ is the area inside the loop. The pdf for the velocity circulation $Γ$ is Lorentzian, with the width $\barΓ \propto A^{\tt} $.

hep-th↗