2025년 03월 QSMS Monthly Seminar
- Date: March 28th (Fri) 14:00 ~ 17:00
- Place: 27-220 (SNU)
- Contents:
Speaker: 유화종 (SNU)
Title: The rational cuspidal subgroup of J_0(N)
Abstract: We introduce generalized Ogg's conjecture which asserts that the rational torsion subgroup of J_0(N) is equal to the rational cuspidal subgroup of J_0(N). And then we discuss how to compute the rational cuspidal subgroup of J_0(N) when N is a prime power.
Speaker: 이석형 (SNU)
Title: On irreducible elements of numerical semigroup algebras
Abstract: A numerical semigroup algebra over a field $F$ is an algebra of the form $F[x^{a_1}, ..., x^{a_k}]$, where $a_1, \ldots, a_k$ are coprime positive integers. Many properties of numerical semigroup algebra can be described via study of the set $S = \{a_1 n_1 + ... + a_k n_k : n_i \in \mathbb{Z}_{\ge 0} \}$, which we call numerical semigroup. We determine asymptotics of the number of irreducible elements of degree n in numerical semigroup algebra over a finite field, in terms of our new combinatorial invariant of the associated numerical semigroup. This is a joint work with Hyunsoo Cho, Kyeongjun Lee and Hayan Nam.