## 過去の記録

#### 保型形式の整数論月例セミナー

13:30-16:00   数理科学研究科棟(駒場) 123号室

### 2014年02月13日(木)

#### 数値解析セミナー

16:00-17:30   数理科学研究科棟(駒場) 056号室
いつもと,開催曜日,開催時刻,教室が異なっております.ご注意ください.
Mitchell Luskin 氏 (University of Minnesota)
Numerical analysis of atomistic-to-continuum coupling methods (ENGLISH)
[ 講演概要 ]
The building blocks of micromechanics are the nucleation and movement of point, line, and surface defects and their long-range elastic interactions. Computational micromechanics has begun to extend the predictive scope of theoretical micromechanics, but mathematical theory able to assess the accuracy and efficiency of multiscale methods is needed for computational micromechanics to reach its full potential.

Many materials problems require the accuracy of atomistic modeling in small regions, such as the neighborhood of a crack tip. However, these localized defects typically interact through long range elastic fields with a much larger region that cannot be computed atomistically. Materials scientists have proposed many methods to compute solutions to these multiscale problems by coupling atomistic models near a localized defect with continuum models where the deformation is nearly uniform on the atomistic scale. During the past several years, a mathematical structure has been given to the description and formulation of atomistic-to-continuum coupling methods, and corresponding numerical analysis and benchmark computational experiments have clarified the relation between the various methods and their sources of error. Our numerical analysis has enabled the development of more accurate and efficient coupling methods.
[ 講演参考URL ]
http://www.infsup.jp/utnas/

### 2014年02月12日(水)

#### 代数幾何学セミナー

14:00-17:30   数理科学研究科棟(駒場) 122号室
いつもと曜日・時間が異なります

An injectivity theorem with multiplier ideal sheaves of singular metrics with transcendental singularities (ENGLISH)
[ 講演概要 ]
In this talk, I give an injectivity theorem with multiplier ideal sheaves of singular metrics.
This theorem is a powerful generalization of various injectivity and vanishing theorems.
The proof is based on a combination of the theory of harmonic integrals and the L^2-method for the \\dbar-equation.
To treat transcendental singularities, after regularizing a given singular metric, we study the asymptotic behavior of the harmonic forms with respect to a family of the regularized metrics.
Moreover we obtain L^2-estimates of solutions of the \\dbar-equation, by using the \\check{C}ech complex.
As an application, we obtain a Nadel type vanishing theorem.
Junyan Cao 氏 (KIAS) 16:00-17:30
Ohsawa-Takegoshi extension theorem for K\\"ahler manifolds (ENGLISH)
[ 講演概要 ]
In this talk, we first prove a version of the Ohsawa-Takegoshi
extension theorem valid for on arbitrary K\\"ahler manifolds, and for
holomorphic line bundles equipped with possibly singular metrics. As an
application, we generalise Berndtsson and Paun 's result about the
pseudo-effectivity of the relative canonical bundles to arbitrary
compact K\\"ahler families.

#### 博士論文発表会

09:30-10:45   数理科学研究科棟(駒場) 118号室

A construction of a universal finite type invariant of homology 3-spheres(ホモロジー3球面の普遍有限型不変量のひとつの構成) (JAPANESE)

#### 博士論文発表会

11:00-12:15   数理科学研究科棟(駒場) 118号室

Congruences of Hilbert modular forms over real quadratic fields and the special values of L-functions(実2次体上のHilbert保型形式の合同式とL関数の特殊値) (JAPANESE)

#### 博士論文発表会

13:00-14:15   数理科学研究科棟(駒場) 128号室

On contact submanifolds of the odd dimensional Euclidean space(奇数次元ユークリッド空間の接触部分多様体について) (JAPANESE)

#### 博士論文発表会

15:00-16:15   数理科学研究科棟(駒場) 128号室

### 2014年02月10日(月)

#### 博士論文発表会

11:00-12:15   数理科学研究科棟(駒場) 118号室

Liouville type theorems for the Navier-Stokes equations andapplications(ナヴィエ・ストークス方程式に対するリウヴィル型定理とその応用)
(JAPANESE)

#### 博士論文発表会

13:00-14:15   数理科学研究科棟(駒場) 118号室

Mathematical and numerical analysis for incompressible fluid equations under friction boundary conditions(摩擦型境界条件下での非圧縮流体の方程式に対する数学解析と数値解析) (JAPANESE)

#### 博士論文発表会

08:00-09:15   数理科学研究科棟(駒場) 128号室

A cellular approach to the Hecke-Clifford superalgebra(セルラー代数の手法によるHecke-Clifford スーパー代数の研究) (JAPANESE)

#### 博士論文発表会

09:30-10:45   数理科学研究科棟(駒場) 128号室

Good reduction criterion for K3 surfaces(K3曲面の良い還元の判定法)
(JAPANESE)

#### 博士論文発表会

13:00-14:15   数理科学研究科棟(駒場) 128号室

Spaces of stability conditions on Calabi-Yau categories associated with quivers(箙に付随するCalabi-Yau圏の安定性条件の空間について)
(JAPANESE)

### 2014年02月05日(水)

#### 代数学コロキウム

17:10-18:10   数理科学研究科棟(駒場) 002号室
いつもと時間・場所が異なりますのでご注意ください
Neven Grbac 氏 (University of Rijeka)
The Franke filtration of spaces of automorphic forms (ENGLISH)
[ 講演概要 ]
The Franke filtration is a filtration of the space of all adelic automorphic forms on a reductive group defined over a number field. The filtration steps can be described as certain induced representations, which has applications to the study of Eisenstein cohomology. In this talk, we shall describe the Franke filtration in general, give several examples, and explain its connection to cohomology.

### 2014年02月03日(月)

#### 代数幾何学セミナー

15:30-17:00   数理科学研究科棟(駒場) 122号室

Classification of log del Pezzo surfaces of index three (JAPANESE)
[ 講演概要 ]
Log del Pezzo surfaces constitute an interesting class of rational surfaces and naturally appear in the minimal model program. I will describe an algorithm to classify all the log del Pezzo surfaces of fixed (Q-Gorenstein) index $a$. Especially, I will focus on the case that $a$ is equal to three. This is joint work with Kazunori Yasutake.

#### GCOEセミナー

16:00-17:00   数理科学研究科棟(駒場) 118号室
Fatiha Alabau 氏 (University of Lorraine)
On the influence of the coupling on the dynamics of under-observed cascade systems of PDE’s (ENGLISH)
[ 講演概要 ]
We consider observability of coupled dynamical systems of hyperbolic and parabolic type when the number of observations is strictly less that the number of unknowns. A main issue is to understand how the lack of observations of certain components is compensated by the coupling information. This talk will present a mathematical approach based on energy methods and some recent positive and negative results on these questions.

#### GCOEセミナー

17:00-18:00   数理科学研究科棟(駒場) 118号室
Piermarco Cannarsa 氏 (University of Rome Tor Vergata)
Compactness estimates for Hamilton-Jacobi equations (ENGLISH)
[ 講演概要 ]
For scalar conservations laws in one space dimension, P. Lax was the first to obtain compactness properties of the solution semigroup. Such properties were subsequently analyzed by several authors in quantitative terms using Kolmogorov's entropy. In this talk, we shall explain how to adapt such approach to the Hopf-Lax semigroup of solutions to first order Hamilton-Jacobi equations in arbitrary space dimension, and discuss related controllability issues.

### 2014年02月01日(土)

#### 保型形式の整数論月例セミナー

13:30-16:00   数理科学研究科棟(駒場) 123号室
Bayarmagnai, G. 氏 (National University of Mongolia) 13:30-14:30
On the three dimensional Whittaker functions on SU(2,2) (ENGLISH)
[ 講演概要 ]
The speaker will discuss the technical aspect to have explicit Whittaker functions belonging to principal series representations of SU(2,2) with non-trivial minimal K-types.

Minimal submanifolds on type IV symmetric domains (ENGLISH)
[ 講演概要 ]
In the explicit constructions of fundamental domains in some typical classical domains with respect standard arithmetic discrete subgroups, there appears real minimal hypersurfaces. But this was known only for real rank one cases. We try to find the situation for the cases of rank 2 by some exapmles.

#### 保型形式の整数論月例セミナー

13:30-16:00   数理科学研究科棟(駒場) 123号室
Bayarmagnai, G. 氏 (National University of Mongolia) 13:30-14:30
On the three dimensional Whittaker functions on SU(2,2) (ENGLISH)
[ 講演概要 ]
The speaker will discuss the technical aspect to have explicit Whittaker functions belonging to principal series representations of SU(2,2) with non-trivial minimal K-types.

Minimal submanifolds on type IV symmetric domains (ENGLISH)
[ 講演概要 ]
In the explicit constructions of fundamental domains in some typical classical domains with respect standard arithmetic discrete subgroups, there appears real minimal hypersurfaces. But this was known only for real rank one cases. We try to find the situation for the cases of rank 2 by some exapmles.

#### 保型形式の整数論月例セミナー

13:30-16:00   数理科学研究科棟(駒場) 123号室
Bayarmagnai, G. 氏 (National University of Mongolia) 13:30-14:30
On the three dimensional Whittaker functions on SU(2,2) (ENGLISH)
[ 講演概要 ]
The speaker will discuss the technical aspect to have explicit Whittaker functions belonging to principal series representations of SU(2,2) with non-trivial minimal K-types.

Minimal submanifolds on type IV symmetric domains (ENGLISH)
[ 講演概要 ]
In the explicit constructions of fundamental domains in some typical classical domains with respect standard arithmetic discrete subgroups, there appears real minimal hypersurfaces. But this was known only for real rank one cases. We try to find the situation for the cases of rank 2 by some exapmles.

#### 保型形式の整数論月例セミナー

13:30-16:00   数理科学研究科棟(駒場) 123号室
Bayarmagnai, G. 氏 (National University of Mongolia) 13:30-14:30
On the three dimensional Whittaker functions on SU(2,2) (ENGLISH)
[ 講演概要 ]
The speaker will discuss the technical aspect to have explicit Whittaker functions belonging to principal series representations of SU(2,2) with non-trivial minimal K-types.

Minimal submanifolds on type IV symmetric domains (ENGLISH)
[ 講演概要 ]
In the explicit constructions of fundamental domains in some typical classical domains with respect standard arithmetic discrete subgroups, there appears real minimal hypersurfaces. But this was known only for real rank one cases. We try to find the situation for the cases of rank 2 by some exapmles.

#### 保型形式の整数論月例セミナー

13:30-16:00   数理科学研究科棟(駒場) 123号室
Bayarmagnai, G. 氏 (National University of Mongolia) 13:30-14:30
On the three dimensional Whittaker functions on SU(2,2) (ENGLISH)
[ 講演概要 ]
The speaker will discuss the technical aspect to have explicit Whittaker functions belonging to principal series representations of SU(2,2) with non-trivial minimal K-types.

Minimal submanifolds on type IV symmetric domains (ENGLISH)
[ 講演概要 ]
In the explicit constructions of fundamental domains in some typical classical domains with respect standard arithmetic discrete subgroups, there appears real minimal hypersurfaces. But this was known only for real rank one cases. We try to find the situation for the cases of rank 2 by some exapmles.

#### 保型形式の整数論月例セミナー

13:30-16:00   数理科学研究科棟(駒場) 123号室
Bayarmagnai, G. 氏 (National University of Mongolia) 13:30-14:30
On the three dimensional Whittaker functions on SU(2,2) (ENGLISH)
[ 講演概要 ]
The speaker will discuss the technical aspect to have explicit Whittaker functions belonging to principal series representations of SU(2,2) with non-trivial minimal K-types.

Minimal submanifolds on type IV symmetric domains (ENGLISH)
[ 講演概要 ]
In the explicit constructions of fundamental domains in some typical classical domains with respect standard arithmetic discrete subgroups, there appears real minimal hypersurfaces. But this was known only for real rank one cases. We try to find the situation for the cases of rank 2 by some exapmles.

#### 保型形式の整数論月例セミナー

13:30-16:00   数理科学研究科棟(駒場) 123号室
Bayarmagnai, G. 氏 (National University of Mongolia) 13:30-14:30
On the three dimensional Whittaker functions on SU(2,2) (ENGLISH)
[ 講演概要 ]
The speaker will discuss the technical aspect to have explicit Whittaker functions belonging to principal series representations of SU(2,2) with non-trivial minimal K-types.

Minimal submanifolds on type IV symmetric domains (ENGLISH)
[ 講演概要 ]
In the explicit constructions of fundamental domains in some typical classical domains with respect standard arithmetic discrete subgroups, there appears real minimal hypersurfaces. But this was known only for real rank one cases. We try to find the situation for the cases of rank 2 by some exapmles.

#### 保型形式の整数論月例セミナー

13:30-16:00   数理科学研究科棟(駒場) 123号室
Bayarmagnai, G. 氏 (National University of Mongolia) 13:30-14:30
On the three dimensional Whittaker functions on SU(2,2) (ENGLISH)
[ 講演概要 ]
The speaker will discuss the technical aspect to have explicit Whittaker functions belonging to principal series representations of SU(2,2) with non-trivial minimal K-types.

Minimal submanifolds on type IV symmetric domains (ENGLISH)
[ 講演概要 ]
In the explicit constructions of fundamental domains in some typical classical domains with respect standard arithmetic discrete subgroups, there appears real minimal hypersurfaces. But this was known only for real rank one cases. We try to find the situation for the cases of rank 2 by some exapmles.

### 2014年01月31日(金)

#### 談話会・数理科学講演会

16:30-17:30   数理科学研究科棟(駒場) 122号室

お茶&Coffee&お菓子: 16:00～16:30 (コモンルーム)。

Jean-Pierre Puel 氏 (Université de Versailles Saint-Quentin-en-Yvelines)
Controllability of fluid flows (ENGLISH)
[ 講演概要 ]
First of all we will describe in an abstract situation the various concepts
of controllability for evolution equations.
We will then present some problems and results concerning the
controllability of systems modeling fluid flows.
First of all we will consider the Euler equation describing the motion of an
incompressible inviscid fluid.
Then we will give some results concerning the Navier-Stokes equations,
modeling an incompressible viscous fluid, and some related systems.
Finally we will give a first result of controllability for the case of a
compressible fluid (in dimension 1) and some important open problems.