Joint Event: Math Department Colloquium & SASA Seminar (Unusual Colloquium Time)

• Árpád Bényi
• Professor
• Western Washington University
• Date: March 23, Monday, 2026
• Time: 14:00-15:00
• Host: Bingyang Hu
• Room: Parker 328
• Abstract: The celebrated theorem of David and Journé from the 80s provides a characterization of the \(L^2\)-boundedness of operators \(T\) with Calderón-Zygmund kernels in terms of appropriate conditions on \(T1\) and \(T^*1\). After recalling this result and some relevant equivalent formulations of it, we discuss several versions of the T1 theorem characterizing the \(L^2\)-compactness of Calderón-Zygmund operators and some of their applications to pseudodifferential operators and commutators. The talk is intended for a general audience, and it is based on some recent joint works with Guopeng Li (Beijing Institute of Technology), Tadahiro Oh (University of Edinburgh) and Rodolfo H. Torres (University of California, Riverside).