3 papers
math.AG2026
A counterexample to a conjecture of Duncan on versal actions
Federico Scavia
We disprove a conjecture of Duncan asserting that versality of a faithful finite group action can be detected on Sylow subgroups. Our counterexample is an action of $(C_7\rtimes C_…
math.AG2026
Zero-cycles on surfaces dominated by products of hyperelliptic curves
Jean-Louis Colliot-Thélène, Federico Scavia, Alexei Skorobogatov
Conditionally on the finiteness of the relevant Tate-Shafarevich groups, we prove a local-to-global result for zero-cycles of degree on the surfaces given by $y^2 = f_1(x_1)f_2…
math.AG2025
Variétés réelles connexes non stablement rationnelles
Jean-Louis Colliot-Thélène, Alena Pirutka, Federico Scavia
Let be the field of real Puiseux series. It is a real closed field. We construct the first examples of smooth intersections of two quadrics in and smooth cubic…