Boyu Zhang

collaborators

5 papers

math.GT2026

Splitting spheres for $S^{2}$ -links in $S^{4}$

Jianfeng Lin, Yi Xie, Boyu Zhang

We prove that every smooth two-component split sphere link $L ⊔ R \subset S^{4}$ admits infinitely many smooth splitting $3$ -spheres that are topologically non-isotopic. This gene…

math.SG2026

Topological symplectic manifolds and bi-Lipschitz structures

Dan Cristofaro-Gardiner, Boyu Zhang

We show that a topological symplectic manifold has a canonically associated bi-Lipschitz structure. As a corollary, we obtain the first examples of non-existence and non-uniqueness…

math.GT2026

Pseudo-isotopies of 3-manifolds with infinite fundamental groups

Jianfeng Lin, Yi Xie, Boyu Zhang

Suppose $Y$ is a compact, connected, oriented 3-manifold possibly with boundary, such that $I ¨ _{1} (Y)$ is infinite. Let $Diff_{\partial} (I \times Y)$ denote the group of…

math.GT2026

Dax invariants, light bulbs, and isotopies of symplectic structures

Jianfeng Lin, Weiwei Wu, Yi Xie +1

This paper addresses several isotopy problems on $4$ -manifolds. First, we classify the isotopy classes of embeddings of $I^£$ in $I^£ \times S^{2}$ that are geometrically dual to $\{\mb…

math.GT2025

On the mapping class groups of 4-manifolds with 1-handles

Jianfeng Lin, Yi Xie, Boyu Zhang

We develop a framework that generalizes Budney-Gabai's $W_{3}$ invariant on $I ¨ _{0} Diff (S^{1} \times D^{3}, \partial)$ to 4-manifolds with 1-handles. As applications, we show that i…

Splitting spheres for S2-links in S4

Topological symplectic manifolds and bi-Lipschitz structures

Pseudo-isotopies of 3-manifolds with infinite fundamental groups

Dax invariants, light bulbs, and isotopies of symplectic structures

On the mapping class groups of 4-manifolds with 1-handles

Splitting spheres for $S^{2}$ -links in $S^{4}$