| 過去の記録 ～03/19 | 今後の予定 03/20～ | 談話会・セミナー ホーム | 東大数理 ホーム | 数理へのアクセス |
| 開催情報 | 月曜日16:40～18:10数理科学研究科棟(駒場) 126号室 |
| 担当者 | 永井保成・中岡宏行 |
16:40 - 18:10 数理科学研究科棟(駒場) 126号室
大川 新之介 氏 (東大数理)
『 Extensions of two Chow stability criteria to positive characteristics 』
I will talk about two results on Chow (semi-)stability of cycles in positive characteristics, which were originally known in characteristic 0. One is on the stability of non-singular projective hypersurfaces of degree greater than 2, and the other is the criterion by Y. Lee in terms of the log canonical threshold of Chow divisor. A couple of examples will be discussed in detail.
16:40 - 18:10 数理科学研究科棟(駒場) 126号室
權業 善範 氏 (東大数理)
『 On weak Fano varieties with log canonical singularities 』
We prove that the anti-canonical divisors of weak Fano
3-folds with log canonical singularities are semiample. Moreover, we consider
semiampleness of the anti-log canonical divisor of any weak log Fano pair
with log canonical singularities. We show semiampleness dose not hold in
general by constructing several examples. Based on those examples, we propose
sufficient conditions which seem to be the best possible and we prove
semiampleness under such conditions. In particular we derive semiampleness of the
anti-canonical divisors of log canonical weak Fano 4-folds whose lc centers
are at most 1-dimensional. We also investigate the Kleiman-Mori cones of
weak log Fano pairs with log canonical singularities.
16:40 - 18:10 数理科学研究科棟(駒場) 126号室
Anne-Sophie Kaloghiros 氏 (RIMS)
『 The divisor class group of terminal Gorenstein Fano 3-folds and rationality questions 』
Let Y be a quartic hypersurface in CP^4 with mild singularities, e.g. no worse than ordinary double points.
If Y contains a surface that is not a hyperplane section, Y is not Q-factorial and the divisor class group of Y, Cl Y, contains divisors that are not Cartier. However, the rank of Cl Y is bounded.
In this talk, I will show that in most cases, it is possible to describe explicitly the divisor class group Cl Y by running a Minimal Model Program (MMP) on X, a small Q-factorialisation of Y. In this case, the generators of Cl Y/ Pic Y are ``topological traces " of K-negative extremal contractions on X.
This has surprising consequences: it is possible to conclude that a number of families of non-factorial quartic 3-folds are rational.
In particular, I give some examples of rational quartic hypersurfaces Y_4\subset CP^4 with rk Cl Y=2 and show that when the divisor class group of Y has sufficiently high rank, Y is always rational.
16:40 - 18:10 数理科学研究科棟(駒場) 126号室
源 泰幸 氏 (京都大学理学部数学教室)
『 Ampleness of two-sided tilting complexes 』
From the view point of noncommutative algebraic geometry (NCAG),
a two-sided tilting complex is an analog of a line bundle.
In this talk we introduce the notion of ampleness for two-sided
tilting complexes over finite dimensional algebras.
From the view point of NCAG, the Serre functors are considered to be
shifted canonical bundles. We show by examples that the property
of shifted canonical bundle captures some representation theoretic
property of algebras.
14:40 - 16:10 数理科学研究科棟(駒場) 126号室
いつもと時間帯が異なります。ご注意ください。
Sergey Galkin 氏 (IPMU)
『 Invariants of Fano varieties via quantum D-module 』
We will introduce and compute Apery characteristic
class and Frobenius genera - invariants of Fano variety derived from
it's Gromov-Witten invariants. Then we will show how to compute them
and relate with other invariants.
16:40 - 18:10 数理科学研究科棟(駒場) 126号室
Colin Ingalls 氏 (University of New Brunswick and RIMS)
『 Rationality of the Brauer-Severi Varieties of Skylanin algebras 』
Iskovskih's conjecture states that a conic bundle over
a surface is rational if and only if the surface has a pencil of
rational curves which meet the discriminant in 3 or fewer points,
(with one exceptional case). We generalize Iskovskih's proof that
such conic bundles are rational, to the case of projective space
bundles of higher dimension. The proof involves maximal orders
and toric geometry. As a corollary we show that the Brauer-Severi
variety of a Sklyanin algebra is rational.
16:40 - 18:10 数理科学研究科棟(駒場) 126号室
Gerard van der Geer 氏 (Universiteit van Amsterdam)
『 Cohomology of moduli spaces of curves and modular forms 』
The Eichler-Shimura theorem expresses cohomology of local systems
on the moduli of elliptic curves in terms of modular forms. The
cohomology of local systems can be succesfully explored by counting
points over finite fields. We show how this can be applied to
obtain a lot of information about the cohomology of other moduli spaces
of low genera and also about Siegel modular forms of genus 2 and 3.
This is joint work with Jonas Bergstroem and Carel Faber.
16:40 - 18:10 数理科学研究科棟(駒場) 126号室
渡辺 究 氏 (早稲田大学基幹理工学研究科)
『 ファノ多様体上の有理曲線の鎖の長さについて 』
ピカール数1のファノ多様体に対し、一般の二点を結ぶために必要な
極小有理曲線の本数を「長さ」と呼び、それについて考える。特に、5次元以下の
ファノ多様体や余指数が3以下のファノ多様体などに対し、長さを求める。
16:40 - 18:10 数理科学研究科棟(駒場) 126号室
伊藤 敦 氏 (東大数理)
『 代数曲面上の随伴束の基底点集合について 』
偏極付き代数多様体上(X,L)は、Lに数値的な条件を付け加えると
その随伴束が自由になったり、基底点集合が具体的にかけることがある。しかし
、曲線の場合は簡単であるが高次元の場合は難しい。今回の講演では主に代数曲
面の場合について解説する。
16:30 - 18:00 数理科学研究科棟(駒場) 002号室
部屋・曜日にご注意ください。
Matthias Schuett 氏 (Leibniz University Hannover)
『 Arithmetic of K3 surfaces 』
This talk aims to review recent developments in the arithmetic of K3 surfaces, with emphasis on singular K3 surfaces.
We will consider in particular modularity, Galois action on Neron-Severi groups and behaviour in families.
16:30 - 18:00 数理科学研究科棟(駒場) 126号室
佐野 太郎 氏 (東大数理)
『 Seshadri constants on rational surfaces with anticanonical pencils 』
射影多様体上の豊富線束の$k$-jet ample性を測る不変量として
Seshadri定数と呼ばれる正の実数がある。
この不変量を調べることでしばしば幾何的な情報が得られる。
今回、1次元以上の反標準線形系をもつ有理曲面上のSeshadri定数を計算する公式
が得られた。
その公式を使うと、対数del Pezzo曲面の特異点の情報をSeshadri定数の値から
復元できる。
16:30 - 18:00 数理科学研究科棟(駒場) 126号室
柳田 伸太郎 氏 (神戸大学理学研究科)
『 アーベル曲面上の安定層とフーリエ向井変換について 』
今回の講演は吉岡康太との共同研究に基づくものである. 研究の発端は, 向井茂が1980年前後(フーリエ向井変換の発見前後)に考察し, 当時の講演記録に書き残した主張や予想の解読にある.
本研究は, 大まかに言うと, 半等質層とフーリエ向井変換を用いて, アーベル曲面上の安定層のモジュライ空間の構造を調べるというものである.
アーベル曲面上には半等質層と呼ばれる半安定層があり, その分類, 構成方法やコホモロジーが完全に知られている. アーベル曲面のフーリエ向井対は半等質層のモジュライ空間であることも知られている.
今回の研究はこの半等質層をbulding blockとして一般の安定層を構成することを考える. その際に"semi-homogeneous presentation"という概念が必要になる. これはアーベル曲面上の安定層の半等質層によるある種の分解のことである. 曲面のピカール数が1の時, この種の分解の存在が安定層のチャーン指標のみを用いて判定できる.
また安定層のフーリエ変換における振舞いの記述において, 算術群や整数係数2次形式が重要な役割を果たすことも分かる. この事と先に述べた表示の存在から, 安定層のモジュライとアーベル曲面上の点のヒルベルトスキームとの間の双有理変換が明示的に構成できる.
アーベル曲面のフーリエ向井変換のフォーマリズムはK3曲面の変換と共通する部分も少なくない. 講演ではそうした点にも触れつつ, 今回の結果とその証明の概要を解説したい.
16:30 - 18:00 数理科学研究科棟(駒場) 126号室
大川 領 氏 (東京工業大学)
『 Moduli on the projective plane and the wall-crossing 』
射影平面上の半安定層のモジュライ空間を、Bridgeland 安定性条件
を用いることにより、ある有限次元代数の半安定表現のモジュライ空間
として構成する。階数が2以下の場合、表現の安定性条件を変化させること
により、壁越え現象としてのflip の記述を得る。
応用として、flip のBetti 数などが計算できる。
16:30 - 18:00 数理科学研究科棟(駒場) 126号室
岸本崇氏 氏 (埼玉大学理工学研究科)
『 Group actions on affine cones 』
The action of the additive group scheme C_+ on normal affine varieties is one of main subjects in affine algebraic geometry for a long time. In this talk, we shall mainly consider the problem about the existence of C_+-actions on affine cones, more precisely, the question:
"Determine the affine cones over smooth projective varieties admitting a (non-trivial) C_+-action ".
This question has an interest from a point of view of singularities. Indeed, a normal Cohen-Macaulay affine variety admitting an action by C_+ has at most rational singularities due to the result of H. Flenner and M. Zaidenberg. In the case of dimension 2, any affine cone over the projective line P^1 has a cyclic quotient singularity, and we can see that it admits, in fact, a C_+-action. Meanwhile, in case of dimension 3, i.e., affine cones over rational surfaces, the situation becomes more subtle.
One of the main results is concerned with a criterion for the existence of a C_+-action on affine cones (of any dimension) in terms of a cylinderlike open subset on the base variety. By making use of it, it is shown that, for any rational surface Y, we can take a suitable embedding of Y in such a way that the associated affine cone admits an action of C_+. Furthermore we are able to confirm that an affine cone over an anticanonically embedded del Pezzo surface of degree greater than or equal to 4 also admits such an action.
Nevertheless, our final purpose to decide whether or not there does exist a C_+-action on the fermat cubic: x^3+y^3+z^3+u^3 =0 in C^4, which is the affine cone over an anticanonically embedded cubic surface, say Y_3, is not yet accomplished. But, we can obtain certain informations about a linear pencil of rational curves on Y_3 arising from a C_+-action which seem to be useful in order to deny an existence of an action of C_+.
16:30 - 18:00 数理科学研究科棟(駒場) 128号室
馬 昭平氏 氏 (東大数理)
『 アーベル曲面の分解と2次形式 』
複素Abel曲面が楕円曲線の積に分解可能である時、分解の仕方は一般に何通りも
ありうる。いくつかの場合に分解の個数公式が求められてきた(林田、塩田-三谷
)。本講演では、すべての分解可能な複素Abel曲面に対して、2次形式論の技法
を用いて分解数の公式を与える。関連して次のことも話す:合同モジュラー曲線
上のAtkin-Lehner対合の幾何学的意味;正定値2元2次形式の類数と判別式形式
の等長群の関係。
15:00 - 16:30 数理科学研究科棟(駒場) 128号室
Prof. Steven Zucker 氏 (Johns Hopkins University)
『 The RBS compactification: a real stratified space in algebraic geometry 』
15:30 - 18:00 数理科学研究科棟(駒場) 122号室
Prof. Alessandra Sarti 氏 (Universite de Poitier) 15:30 - 16:30
『 Automorphism groups of K3 surfaces 』
I will present recent progress in the study of prime order automorphisms of K3 surfaces.
An automorphism is called (non-) symplectic if the induced
operation on the global nowhere vanishing holomorphic two form
is (non-) trivial. After a short survey on the topic, I will
describe the topological structure of the fixed locus, the
geometry of these K3 surfaces and their moduli spaces.
Prof. Samuel Boissier 氏 (Universite de Nice ) 17:00 - 18:00
『 The cohomological crepant resolution conjecture 』
The cohomological crepant resolution conjecture is one
form of Ruan's conjecture concerning the relation between the
geometry of a quotient singularity X/G - where X is a smooth
complex variety and G a finite group of automorphisms - and the
geometry of a crepant resolution of singularities of X/G ; it
generalizes the classical McKay correspondence. Following the
examples of the Hilbert schemes of points on surfaces and the
weighted projective spaces, I will present some of the recents
developments of the subject.
15:50 - 18:00 数理科学研究科棟(駒場) 128号室
O. F. Pasarescu 氏 (Romanian Academy)
『 ・Linear Systems on Rational Surfaces; Applications (15:50--16: 50) ・Some Applications of Model Theory in Algebraic Geometry (17:00 --18:00) 』
16:30 - 18:00 数理科学研究科棟(駒場) 122号室
Piotr Pragacz 氏 (Banach Institute)
『 Diagonal subschemes and vector bundles 』
16:30 - 18:00 数理科学研究科棟(駒場) 118号室
Xavier Roulleau 氏 (東大)
『 Cotangent maps of surfaces of general type 』
Surfaces are usualy studied and classified via the properties of the pluricanonical maps. For surfaces of general type whose cotangent sheaf is generated by global sections, we propose to study an other map, called the cotangent map, in order to obtain geometric informations on the surface. In this way, we obtain informations on the ampleness of the cotangent sheaf of such a surface. We will illustate this talk with the example of the Fano surface of lines of cubic threefolds.
16:30 - 18:00 数理科学研究科棟(駒場) 118号室
Misha Verbitsky 氏 (ITEP and IPMU)
『 Hyperkaehler SYZ conjecture and stability 』
Let L be a nef bundle on a hyperkaehler manifold. A Hyperkaehler SYZ conjecture postulates that L is semi-ample. As shown by Matsushita, this implies existence of holomorphic Lagrangian fibrations on hyperkaehler manifolds. It was conjectured by many
people, most recently by Tschinkel, Hassett, Huybrechts and Sawon. We prove that a sufficiently big power of L is effective, assuming that L admits a semi-positive metric. A multiplier ideal version of this argument would give effectivity of L^N for any nef L. The proof uses stability and Boucksom's divisorial
Zariski decomposition.
13:00 - 14:30 数理科学研究科棟(駒場) 128号室
Yongnam Lee 氏 (Sogang U.)
『 Construction of surfaces of general type with pg=0 via Q-Gorenstein smoothing 』
16:30 - 18:00 数理科学研究科棟(駒場) 122号室
高木寛通 氏 (東大数理)
『 Scorza quartics of trigonal spin curves and their varieties of power sums 』
Our fundamental result is the construction of new subvarieties in the varieties of power sums for the Scorza quartic of any general pairs of trigonal curves and non-effective theta characteristics. This is a generalization of Mukai's description of smooth prime Fano threefolds of genus twelve as the varieties of power sums for plane quartics. Among other applications, we give an affirmative answer to the conjecture of Dolgachev and Kanev on the existence of the Scorza quartic for any general pairs of curves and non-effective theta characteristics.
16:30 - 18:00 数理科学研究科棟(駒場) 126号室
David Morrison 氏 (UC Santa Barbara)
『 Understanding singular algebraic varieties via string theory 』
String theory has helped to formulate two major new insights in the study of singular algebraic varieties. The first -- which also arose from symplectic geometry -- is that families of Kaehler metrics are an important tool in uncovering the structure of singular algebraic varieties. The second, more recent insight -- related to independent work in the representation theory of associative algebras -- is that one's understanding of a singular (affine) algebraic variety is enhanced if one can find a non-commutative ring whose center is the coordinate ring of the variety. We will describe both of these insights, and explain how they are related to string theory.
10:00 - 12:00 数理科学研究科棟(駒場) 128号室
Dmitry KALEDIN 氏 (Steklov研究所, 東大数理)
『 Homological methods in non-commutative geometry, part 11 (last lecture) 』
http://imperium.lenin.ru/~kaledin/math/tokyo/
10:00 - 12:00 数理科学研究科棟(駒場) 128号室
Dmitry KALEDIN 氏 (Steklov研究所, 東大数理)
『 Homological methods in non-commutative geometry, part 10 』
10:00 - 12:00 数理科学研究科棟(駒場) 128号室
Dmitry KALEDIN 氏 (Steklov研究所, 東大数理)
『 Homological methods in non-commutative geometry, part 9 』
10:00 - 12:00 数理科学研究科棟(駒場) 128号室
Dmitry KALEDIN 氏 (Steklov研究所, 東大数理)
『 Homological methods in non-commutative geometry, part 8 』
10:00 - 12:00 数理科学研究科棟(駒場) 128号室
次回は2008年1月8日です.
Dmitry KALEDIN 氏 (Steklov研究所, 東大数理)
『 Homological methods in non-commutative geometry, part 7 』
16:30 - 18:00 数理科学研究科棟(駒場) 122号室
Alexander Kuznetsov 氏 (Steklov Inst)
『 Categorical resolutions of singularities 』
I will give a definition of a categorical resolution of singularities and explain how such resolutions can be constructed.
16:30 - 18:00 数理科学研究科棟(駒場) 118号室
Alexandru DIMCA 氏 (Univ Nice )
『 New restrictions on the fundamental groups of complex algebraic varieties 』
My talk will be based on joint work with S. Papadima (Bucarest, Romania) and A. Suciu (Boston, USA). First I will recall the basic facts on characteristic varieties $V_k(M)$ associated to rank one local systems on a complex algebraic variety $M$ which are due to Beauville, Simpson and Arapura. Then I will introduce the resonance varities $R_k(M)$, which may be related to the Isotropic Subspace Theorems by Catanese and Bauer. One of the main new results is that for a class of algebraic varieties (the 1-formal ones), the two types of varieties $V_k(M)$ and $R_k(M)$ are strongly related. Applications to right angle Artin groups, Bestvina-Brady groups and to a conjecture by Kollar will be discussed in the end.
10:00 - 12:00 数理科学研究科棟(駒場) 128号室
毎週火曜10時から12時の連続講演の第2回目です. 10月23日と12月4日は休講です.
第1回目の講義ノートがhttp://imperium.lenin.ru/~kaledin/math/tokyo/にあります.
Dmitry KALEDIN 氏 (Steklov研究所, 東大数理)
『 Homological methods in Non-commutative Geometry 』
10:00 - 12:00 数理科学研究科棟(駒場) 128号室
10月16日開始, 毎週火曜10時から12時の連続講演です. 10月23日と12月4日は休講です.
Dmitry KALEDIN 氏 (Steklov研究所, 東大数理)
『 Homogical methods in Non-commutative Geometry 』
Of all the approaches to non-commutative geometry, probably the most promising is the homological one, developed by Keller, Kontsevich, Toen and others, where non-commutative eometry is understood as "geometry of triangulated categories". Examples of "geometric" triangulated categories come from representation theory, symplectic geometry (Fukaya category) and algebraic geometry (the derived category of coherent sheaves on an algebraic variety and
various generalizations). Non-commutative point of view is expected to be helpful even in traditional questions of algebraic geometry such as the termination of flips.
We plan to give an introduction to the subject, with emphasis on homological methods (such as e.g. Hodge theory which, as it turns out, can be mostly formulated in the non-commutative setting).
No knowledge of non-commutative geometry whatsoever is assumed. However, familiarity with basic homological algebra and algebraic geometry will be helpful.
16:30 - 17:30 数理科学研究科棟(駒場) 117号室
代数学コロキウムとの合同講演会です. 15時から122号室でKaledinさんの講演があります.
James Lewis 氏 (University of Alberta)
『 Abel-Jacobi Maps Associated to Algebraic Cycles, I. 』
This talk concerns the Bloch cycle class map from the higher Chow groups to Deligne cohomology of a projective algebraic manifold. We provide an explicit formula for this map in terms of polylogarithmic type currents.
15:00 - 16:00 数理科学研究科棟(駒場) 122号室
Dmitry Kaledin 氏 (Steklov Institute)
『 p-adic Hodge theory in the non-commutative setting 』
We will explain what is the natural replacement of the notion of Hodge structure in the p-adic setting, and how to construct such a structure for non-commutative manifolds (something which at present cannot be done for the usual Hodge structures, but works perfectly well for the p-adic analog).
16:30 - 18:00 数理科学研究科棟(駒場) 126号室
Grigory Mikhalkin 氏 (Toronto大学)
『 Floor diagrams and enumeration of tropical curves 』
The enumerative problems considered in this talk are finding the number of curves in projective spaces (over complex, real and tropical numbers) of given genus and degree constrained by certain incidence conditions (e.g. passing via points or lines). Floor diagrams are a combinatorial tool that reduces an enumerative problem in dimension n to the corresponding problem n dimension n-1. Floor diagrams give a constructive (and rather efficient) way to find all tropical curves for a given enumerative problem. And once we have a tropical solution of the problem we can use it to solve the corresponding problems over the complex and real numbers.
15:00 - 18:00 数理科学研究科棟(駒場) 117号室
代数学コロキウムとの合同講演会です.
E. Lau 氏 (Univ. of Bielefeld) 15:00 - 15:45
『 Classification of p-divisible groups by displays and duality 』
T. Zink 氏 (Univ. of Bielefeld) 16:00 - 16:45
『 Applications of the theory of displays 』
E. Looijenga 氏 (Univ. of Utrecht) 17:00 - 18:00
『 Presentation of mapping class groups from algebraic geometry 』
A presentation of the mapping class group of a genus g surface with one hole is due to Wajnryb with later improvements due to M. Matsumoto. The generators are Dehn twists defined by 2g+1 closed curves on the surface. The relations involving only two Dehn twists are the familiar Artin relations, we show that those involving more than two can be derived from algebro-geometry considerations.
17:00 - 18:00 数理科学研究科棟(駒場) 128号室
Valery Alexeev 氏 (Georgia大学)
『 Computations on the moduli spaces of weighted log pairs 』
16:30 - 18:00 数理科学研究科棟(駒場) 126号室
De-Qi Zhang 氏 (Singapore大学)
『 Dynamics of automorphisms on algebraic varieties 』
The building blocks of automorphisms / endomorphisms of compact varieties are determined --- an algebro geometric approach towards dynamics.
16:30 - 18:00 数理科学研究科棟(駒場) 118号室
Qi Zhang 氏 (Missouri大学)
『 Projective varieties with nef anti-canonical divisors 』
Projective varieties with nef anti-canonical divisors appear naturally in the minimal model program and the theory of classification of higher-dimensional algebraic varieties. In this talk we describe a comprehensive approach to birational geometry of log canonical pair (X, D) with nef anti-canonical class -(K_X+D). In particular, We present two theorems on the birational structure of the varieties. We will also discuss some recent results and new aspects of the subject.
14:30 - 16:00 数理科学研究科棟(駒場) 122号室
いつもと時間・曜日・場所が異なります。
Mikhail Kapranov 氏 (Yale 大学)
『 Riemann-Roch for determinantal gerbes and smooth manifolds 』
A version of the Riemann-Roch theorem for curves due to Deligne, describes the determinant of the cohomology of a vector bundle E on a curve.
If one realizes E via the Krichever construction, the determinant of the cohomology becomes a Hom-space in the determinantal gerbe for the vector space over the field of power series. So one has a ``local" Riemann-Roch problem of description of this gerbe itself. The talk will present the results of a joint work with E. Vasserot describing the class of such a gerbe in a family which geometrically can be seen as a circle fibration. This can be further generalized to the case of a fibration with fibers being smooth compact manifolds of any dimension d (joint work with P. Bressler, B. Tsygan and E. Vasserot).
16:30 - 18:00 数理科学研究科棟(駒場) 122号室
謝啓鴻(Xie Qihong) 氏 (東大・数理)
『 Pathologies on ruled surfaces in positive characteristic 』
We discuss some pathologies of log varieties in positive characteristic. Mainly, we show that on ruled surfaces there are counterexamples of several logarithmic type theorems. On the other hand, we also give a characterization of the counterexamples of the Kawamata-Viehweg vanishing theorem on a geometrically ruled surface by means of the Tango invariant of the base curve.
15:30 - 17:00 数理科学研究科棟(駒場) 128号室
Professor Caucher Birkar 氏 (University of Cambridge)
『 Existence of minimal models and flips (3rd talk of three) 』
10:30 - 12:00 数理科学研究科棟(駒場) 128号室
Professor Caucher Birkar 氏 (University of Cambridge)
『 On boundedness of log Fano varieties (2nd talk of three) 』
16:30 - 18:00 数理科学研究科棟(駒場) 128号室
Professor Caucher Birkar 氏 (University of Cambridge )
『 Singularities and termination of flips (1st talk of three) 』
16:30 - 17:30 数理科学研究科棟(駒場) 128号室
Professor Frans Oort 氏 (Department of Mathematics University of Utrecht )
『 Irreducibility of strata and leaves in the moduli space of abelian varieties I (a survey of results) 』
15:00 - 16:25 数理科学研究科棟(駒場) 126号室
Stefan Kebekus 氏 氏 (Mathematisches Institut Universität zu Köln )
『 Rationally connected foliations 』
16:30 - 18:00 数理科学研究科棟(駒場) 126号室
Professor Burt Totaro 氏 (University of Cambridge)
『 When does a curve move on a surface, especially over a finite field? 』
16:30 - 18:00 数理科学研究科棟(駒場) 126号室
青木昌雄 氏 (京大数理研)
『 Hom stacks and Picard stacks 』
16:00 - 18:15 数理科学研究科棟(駒場) 122号室
E. Esteves 氏 (IMPA) 16:00 - 17:00
『 Jets of singular foliations and applications to curves and their moduli spaces 』
F. Zak 氏 (Independent Univ. of Moscow) 17:15 - 18:15
『 Dual varieties, ramification, and Betti numbers of projective varieties 』