Extending periodic maps on surfaces over the 4-sphere

Abstract

Let $F_g$ be the closed orientable surface of genus $g$. We address the problem to extend torsion elements of the mapping class group $\mathcal{M}(F_g)$ over the 4-sphere $S^4$. Let $w_g$ be a torsion element of maximum order in $\mathcal{M}(F_g)$. Results including: (1) For each $g$, $w_g$ is periodically extendable over $S^4$ for some non-smooth embedding $e:F_g\to S^4$, and not periodically extendable over $S^4$ for any smooth embedding $e:F_g\to S^4$. (2) For each $g$, $w_g$ is extendable over $S^4$ for some smooth embedding $e:F_g\to S^4$ if and only if $g=4k,4k+3$. (3) Each torsion element of order $p$ in $\mathcal{M}(F_g)$ is extendable over $S^4$ for some smooth embedding $e:F_g\to S^4$ if either (i) $p=3^m$ and $g$ is even; or (ii) $p=5^m$ and $g\ne 4k+2$; or (iii) $p=7^m$. Moreover the conditions on $g$ in (i) and (ii) can not be removed .

22 pages, 3 figures. To appear in Journal of Topology and Analysis

References in corpus (2)

• On diffeomorphisms over surfaces trivially embedded in the 4-sphere
• Extending periodic automorphisms of surfaces to 3-manifolds

Cited by in corpus (1)

• Knotted surfaces, Homological Norm and Extendable Subgroup