English

On $C^1$, $C^2$, and weak type-$(1,1)$ estimates for linear elliptic operators

Analysis of PDEs 2017-10-13 v3

Abstract

We show that any weak solution to elliptic equations in divergence form is continuously differentiable provided that the modulus of continuity of coefficients in the L1L^1-mean sense satisfies the Dini condition. This in particular answers a question recently raised by Yanyan Li and allows us to improve a result of Brezis. We also prove a weak type-(1,1)(1,1) estimate under a stronger assumption on the modulus of continuity. The corresponding results for non-divergence form equations are also established.

Keywords

Cite

@article{arxiv.1607.04361,
  title  = {On $C^1$, $C^2$, and weak type-$(1,1)$ estimates for linear elliptic operators},
  author = {Hongjie Dong and Seick Kim},
  journal= {arXiv preprint arXiv:1607.04361},
  year   = {2017}
}

Comments

17 pages; accepted in Communications in Partial Differential Equations; minor changes in text

R2 v1 2026-06-22T14:55:24.732Z