Some problems in harmonic analysis

The principal investigator (PI) intends to delve into challenges situated at the junction of harmonic analysis, number theory, and dispersive equations. In addition to focusing on classical Fourier analysis, the PI aims to establish connections with diverse fields, including number theory, combinatorics, dispersive equations on tori, and Ergodic theory. Furthermore, the PI plans to mentor students, disseminate their findings through talks, and foster collaborations, thereby generating broader impacts. The PI plans to continue the research efforts in several areas. Firstly, the PI and his collaborators will delve into the rapidly advancing field of modern mathematics, particularly focusing on additive combinatorics alongside Fourier analysis. Within this realm, they aim to further explore Roth's theorem, a fundamental result that determines the minimum subset size required for the existence of arithmetic progressions within {1, ..., N}. Their work will extend their previous investigations into the polynomial Roth theorem on rings and/or finite fields. Secondly, in classical harmonic analysis, the PI is dedicated to investigating the conjectured pointwise convergence of the Bochner-Riesz mean on the plane, as proposed by Sogge and Tao. Thirdly, in collaboration with Yang, the PI has made strides in improving both Gauss's circle problem and Dirichlet's divisor problem. They believe there is still room for additional progress in these areas. Finally, the PI will continue his study of the Waring problem, which can be approached as a decoupling problem for a function whose Fourier transform is confined to a broken line. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.