# 広島大学理学部数学科 代数数理講座

## 2018年度の代数学セミナー

### 今後の予定

1026（金）15

Moduli of K3 surfaces as moduli of A-infinity structures
We show that moduli spaces of lattice polarized K3 surfaces associated with exceptional unimodal singularities arise as moduli spaces of A-infinity structures on particular finite-dimensional graded algebras.
This is a joint work with Yanki Lekili.
112（金）1620 分　於 B707 号室 いつもと場所と時間が違います。

### これまでの記録

511（金）15

525（金）15

On an exact sequence relating the combinatorial anabelian geometry of hyperbolic curves
In this talk, I survey the combinatorial anabelian geometry of hyperbolic curves, and discuss an exact sequence relating the combinatorial anabelian geometry.
615（金）1620 第2ターム中はいつもと時間が違います。

Dedekind環の無限次拡大環の分数イデアルと上半連続関数のモノイドについて

720（金）1620 第2ターム中はいつもと時間が違います。
Noriko Yui 氏 (Queen's University)
Supercongruences for rigid hypergeometric Calabi–Yau threefolds
I will cosider the 14 one-parameter families of Calabi–Yau threefolds deﬁned over $\mathbb{Q}$, which are realized as mirrors of another one-parameter families of Calabi–Yau threefolds with the Hodge number $h^{1,1}=1$. The Picard–Fuchs diﬀerential equations of these mirror families are of order 4 of hypergeometric type. At a special ﬁber, these mirror Calabi–Yau threefolds will become rigid, i.e., $h^{2,1}=0$. These are the 14 rigid hypergeometric Calabi-Yau threefolds in the title.
In this talk, I will present two proofs to the supercongruences for the 14 rigid hypergeometric CalabiYau threefolds deﬁned over $\mathbb{Q}$. One proof is based on Dwork’s theory of unit roots, and the other one on hypergeometric motives. The existence of such supercongruences was conjectured (based on numerical evidence) by F. Rodriguez-Villegas in 2003.
This is a joint work with Ling Long, Fang-Ting Tu and Wadim Zudilin.