activity
20242026
collaborators

7 papers

math.PR2026

Superdiffusion and anomalous regularization in self-similar random incompressible flows

Scott Armstrong, Ahmed Bou-Rabee, Tuomo Kuusi

We study the long-time behavior of a particle in , , subject to molecular diffusion and advection by a random incompressible flow. The velocity field is the…

math.AP2026

Coarse-grained ellipticity and De Giorgi-Nash-Moser theory

Scott Armstrong, Benny Avelin, Cristiana De Filippis +2

We prove local boundedness and a Harnack inequality for nonnegative weak solutions of the equation under a coarse-grained ellipticity assump…

math.PR2025

1D stochastic pressure equation with log-correlated Gaussian coefficients

Benny Avelin, Tuomo Kuusi, Patrik Nummi +3

We study unique solvability for one dimensional stochastic pressure equation with diffusion coefficient given by the Wick exponential of log-correlated Gaussian fields. We prove we…

math.AP2025

A coarse-graining theory for elliptic operators and homogenization in high contrast

Scott Armstrong, Tuomo Kuusi

We review a coarse-graining theory for divergence-form elliptic operators. The construction centers on a pair of coarse-grained matrices defined on spatial blocks that encode a sca…

math.PR2025

Renormalization group and elliptic homogenization in high contrast

Scott Armstrong, Tuomo Kuusi

We prove a quantitative estimate for the homogenization length scale in terms of the ellipticity ratio of the coefficient field. This upper bound applies to high-contrast e…

math.PR2025

Renormalized stochastic pressure equation with log-correlated Gaussian coefficients

Benny Avelin, Tuomo Kuusi, Patrik Nummi +3

We study periodic solutions to the following divergence-form stochastic partial differential equation with Wick-renormalized gradient on the -dimensional flat torus $\mathbb{T}^…