Qiuyu Ren

Qiuyu Ren will receive his PhD in 2026 from UC Berkeley, where he works under the supervision of Ian Agol. Qiuyu has been appointed as a Clay Research Fellow for five years beginning 1 July 2026.

Ren’s work as a doctoral student has already had a significant impact across low dimensional topology, combinatorics, and spectral theory. Most significantly, in a spectacular work with Willis, he achieved a goal that had eluded leading researchers in four-dimensional manifold theory for many years: the detection of exotic smooth structures on compact four-manifolds using combinatorial methods (as opposed to analytic ones). To achieve this, Ren and Willis showed that the skein lasagna module (a four-manifold invariant derived from Khovanov homology) can take different values on a pair of homeomorphic, compact four-manifolds with boundary. This breakthrough builds on Ren’s earlier work in knot theory, wherein he developed new computational methods for the Khovanov-Lee homology of cables, and proved an adjunction inequality for the Rasmussen invariant. 

Photo: Zhongkai Tao