3 papers
math.AG2026
On the universal curve with unordered marked points in positive characteristic
Ma Luo, Tatsunari Watanabe
We study the relative pro- and continuous relative completions of the algebraic fundamental groups of universal curves over the moduli stack of curves with unordered marked p…
math.AG2025
On the Universal Curves with Unordered Marked Points
Tatsunari Watanabe, Ma Luo
Over any field of characteristic , we prove that the homotopy exact sequence of algebraic fundamental groups for the universal curve with unordered marked points does not split.…
math.AT2025
On the Birman exact sequence of the subgroups of the mapping class group of genus three
Ma Luo, Tatsunari Watanabe
We prove that for any finite index subgroup of the mapping class group containing the Johnson subgroup, the profinite Birman exact sequence does not split in genus , extend…