The Bilinear Bochner-Riesz Operator at the Critical Index

Abstract

We study boundedness properties for the bilinear Bochner-Riesz operator at the critical index. Starting from the weighted estimate previously established by Jotsaroop, Shrivastava, and Shuin, we develop a technique that combines quantitative bilinear Rubio de Francia extrapolation with a suitable bilinear version of Yano’s extrapolation theorem. This method yields a range of new weighted endpoint estimates. Our results cover all open endpoints and include both one-weight and two-weight inequalities.