3 papers
math.AG2025
Welschinger--Witt invariants
Erwan Brugallé, Johannes Rau, Kirsten Wickelgren
Welschinger invariants are signed counts of real rational curves satisfying contraints. Quadratic Gromov--Witten invariants give such counts over general fields of characteristic d…
math.AG2025
A quadratic Abramovich-Bertram formula
Erwan Brugallé, Kirsten Wickelgren
Quadratic Gromov--Witten invariants allow one to obtain an arithmetically meaningful count of curves satisfying constraints over a field without assuming that is the field…
math.AG2024
Bitangents of real algebraic curves: signed count and constructions
Thomas Blomme, Erwan Brugallé, Cristhian Garay
We study real bitangents of real algebraic plane curves from two perspectives. We first show that there exists a signed count of such bitangents that only depends on the real topol…