Improved $A_1-A_\infty$ and related estimates for commutators of rough singular integrals

Abstract

An $A_1-A_\infty$ estimate improving a previous result in arXiv:1607.06432 is obtained. Also new a result in terms of the ${A_\infty}$ constant and the one supremum $A_q-A_\infty^{\exp}$ constant, is proved, providing a counterpart for the result obained in arXiv:1705.08364. Both of the preceding results rely upon a sparse domination in terms of bilinear forms for $[b,T_\Omega]$ with $\Omega\in L^\infty(\mathbb{S}^{n-1})$ and $b\in BMO$ which is established relying upon techniques from arXiv:1705.07397.