3 papers
math.AG2023
Remarks on the sections of universal hyperelliptic curves
Tatsunari Watanabe
In this paper, we study the obstruction for the sections of the universal hyperelliptic curves of genus . The obstruction of our interest comes from the relative completio…
math.AG2023
Non-abelian cohomology of universal curves in positive characteristic
Tatsunari Watanabe
In this paper, we will compute the non-abelian cohomology of the universal complete curve in positive characteristic. This extends Hain's result on the non-abelian cohomology of ge…
math.AG2023
Remarks on Collino cycles and hyperelliptic Johnson homomorphisms
Ma Luo, Tatsunari Watanabe
A Collino cycle is a higher cycle on the Jacobian of a hyperelliptic curve. The universal family of Collino cycles naturally gives rise to a normal function, whose induced monodrom…