Cohomological invariants of root stacks and admissible double coverings

TL;DR

This paper provides a formula for cohomological invariants of root stacks and applies it to compute invariants and the Brauer group of the stack of admissible double coverings, advancing understanding in algebraic geometry.

Contribution

It introduces a new formula for cohomological invariants of root stacks and applies it to specific stacks related to double coverings, offering novel computational tools.

Findings

Derived a formula for cohomological invariants of root stacks

Computed the invariants and Brauer group of admissible double coverings

Enhanced methods for studying algebraic stacks in geometry

Abstract

We give a formula for the cohomological invariants of a root stack, which we apply to compute the cohomological invariants and the Brauer group of the stack of admissible double coverings.