activity
20062026
most citedBurkholder integrals, Morrey's problem and quasiconformal mappings

21 citations · 141 across the 22 of their papers we have counts for

collaborators

23 papers

math.CV2026

Sharp Higher Integrability Theory, Part I: The -norm of the Beurling--Ahlfors transform

Andrea Agazzi, Kari Astala, Giuseppe Bruno +18

We confirm a conjecture posed by T. Iwaniec in 1982: the norm of the Beurling--Ahlfors transform is if , and if .

math.CV2020

Homogenization of iterated singular integrals with applications to random quasiconformal maps

Kari Astala, Steffen Rohde, Eero Saksman +1

We study homogenization of iterated randomized singular integrals and homeomorphic solutions to the Beltrami differential equation with a random Beltrami coefficient. More precisel…

math.AP2020

Dimer Models and Conformal Structures

Kari Astala, Erik Duse, István Prause +1

In this work we study the variational problem associated to dimer models, a class of models from integrable probability and statistical mechanics in dimension two which have been t…

math.CV2019★ 4 cited

Improved Hölder regularity for strongly elliptic PDEs

Kari Astala, Albert Clop, Daniel Faraco +2

We establish surprising improved Schauder regularity properties for solutions to the Leray-Lions divergence type equation in the plane. The results are achieved by studying the non…

math.AP2019★ 1 cited

Global smoothness of quasiconformal mappings in the Triebel-Lizorkin scale

Kari Astala, Martí Prats, Eero Saksman

We study quasiconformal mappings in planar domains and their regularity properties described in terms of Sobolev, Bessel potential or Triebel-Lizorkin scales. This leads to opt…

math.CV2015★ 14 cited

Nonlinear Beltrami operators, Schauder estimates and bounds for the Jacobian

Kari Astala, Albert Clop, Daniel Faraco +2

We provide Schauder estimates for nonlinear Beltrami equations and lower bounds of the Jacobians for homeomorphic solutions. The results were announced in arXiv:1412.4046 but here…