2026/07/28 by Qiuyu Ren, Fang-Rong Zhan
Mathematics · #math.GT #math.QA
We show that rim surgery on a smooth, oriented, properly embedded surface in B4 does not change the map on Khovanov homology induced by the surface, answering a question raised by Hayden and Sundber. More generally, the same insensitivity holds for a class of local surgery operations that we call local annulus replacements. Combined with the work of Hayden--Sundberg, this result yields exotic pairs of surfaces in B4 that cannot be related by any sequence of local annulus replacements. We give two proofs, both making essential use of Khovanov skein lasagna modules.