Keller-Segel type approximation for nonlocal Fokker-Planck equations in one-dimensional bounded domain

Abstract: Numerous evolution equations with nonlocal convolution-type interactions have been proposed. In some cases, a convolution was imposed as the velocity in the advection term. Motivated by analyzing these equations, we approximate advective nonlocal interactions as local ones, thereby converting the effect of nonlocality. In this study, we investigate whether the solution to the nonlocal Fokker-Planck equation can be approximated using the Keller-Segel system. By singular limit analysis, we show that this approximation is feasible for the Fokker-Planck equation with any potential and that the convergence rate is specified. Moreover, we provide an explicit formula for determining the coefficient of the Lagrange interpolation polynomial with Chebyshev nodes. Using this formula, the Keller-Segel system parameters for the approximation are explicitly specified by the shape of the potential in the Fokker-Planck equation. Consequently, we demonstrate the relationship between advective nonlocal interactions and a local dynamical system.