3 papers
math.AG2025
Miyaoka's bound for conics on K3 surfaces and beyond
SÅawomir Rams, Matthias Schütt
We show that Miyaoka's bound for the number of conics on a degree-2h K3 surface is attained for high h, and analogously for higher even degree (smooth) rational curves.
math.AG2024
The 2-divisibility of divisors on K3 surfaces in characteristic 2
Toshiyuki Katsura, Shigeyuki KondÅ, Matthias Schütt
We show that K3 surfaces in characteristic 2 can admit sets of disjoint smooth rational curves whose sum is divisible by 2 in the Picard group, for each . More pr…
math.AG2024
Normal forms for quasi-elliptic Enriques surfaces and applications
Toshiyuki Katsura, Matthias Schütt, Matthias Schütt
We work out normal forms for quasi-elliptic Enriques surfaces and give several applications. These include torsors and numerically trivial automorphisms, but our main application i…