Date: Fri Oct 16 10:12:00 GMT 2015
From: sumio yamada
Subject: 日仏共同研究(タイヒミュラー空間と写像類群)による小研究集会のご案内
皆様、

以下のお知らせを送らせていただきます。よろしくお願い致します。

山田澄生

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メーリングリストの皆様、

重複ご海容ください。
日仏共同研究(タイヒミュラー空間と写像類群)による小研究集会を
11月16日(月)から20日(金)まで
東京大学大学院数理科学研究科 002 号室で
以下の要領で行います。使用言語は英語です。
皆様奮ってご参加ください。

とりいそぎ
大鹿健一(阪大理)
逆井卓也(東大数理)
河澄響矢(東大数理)

=========================
Atelier de travail franco-japonais sur la géométrie
des groupes modulaires et des espaces de Teichmüller

Les 16-20 novembre 2015
Salle 002, Faculté de sciences mathématiques, Université de Tokyo


Le lundi 16 novembre

(10:30-12:00  Salle 128
(Séminaire sur l'analyse géométrique complexe:
(Hideki Miyachi (Université d’Osaka)

13:30-14:30
Athanase Papadopoulos (Université de Strasbourg/CNRS)
Timelike geometry


Le mardi 17 novembre

10:00-11:00
Athanase Papadopoulos (Université de Strasbourg/CNRS)
Spherical geometry I

11:30-12:30
Takahito Naito (Université de Tokyo)
Sullivan's coproduct on the relative loop homology

14:00-15:00 + 15:30-16:30
Gwénaël Massuyeau (Université de Strasbourg/CNRS)
Fox pairings in Hopf algebras and Poisson structures

(16:30-17:00 Salle commune 
(pause café pour Séminaire du mardi sur la topologie

(17:00-18:30 Salle 056
(Séminaire du mardi sur la topologie
(Atsuko Katanaga (Université de Shinshu)


Le mercredi 18 novembre

10:00-11:00
Athanase Papadopoulos (Université de Strasbourg/CNRS)
Spherical geometry II

11:30-12:30
Yasuo Wakabayashi (Université de Tokyo)
A theory of dormant opers

Le jeudi 19 novembre

10:00-11:00
Masatoshi Sato (Tokyo Denki University)
On the cohomology ring of the handlebody mapping class group of genus two

11:30-12:30
Elena Frenkel (Université de Strasbourg)
Area formula for Hyperbolic Triangles and Lexell problem

14:00-15:00
Yuanyuan Bao (Université de Tokyo)
Heegaard Floer homology for transverse graphs with sinks and sources

15:30-16:30
Tadayuki Watanabe (Université de Shimane)
An invariant of fiberwise Morse functions on surface bundle over S^1 by
counting graphs

Le vendredi 20 novembre

09:30-10:30 + 11:00-12:00
Olivier Guichard (Université de Strasbourg)
Compactifications of certain locally symmetric spaces

(Les 20 à 22 novembre Salle 123
(Rigidity School, Tokyo 2015


=======
Résumés des exposés


Papadopoulos: Timelike geometry
Papadopoulos: Spherical geometry I


Naito: Sullivan's coproduct on the relative loop homology

Sullivan's coproduct is the coproduct on the relative homology of the
free loop space of a closed oriented manifold (called the relative loop
homology). It is known that the relative loop homology is an
infinitesimal bialgebra with respect to this coproduct and the loop
product. In this talk, we will give a homotopical description of
Sullivan's coproduct and introduce its properties. Moreover, we will
compute the coalgebra structure of spheres over the rational number
field by using the description.


Massuyeau: Fox pairings in Hopf algebras and Poisson structures

We will present the general theory of Fox pairings in Hopf algebras, which
will be illustrated through several algebraic examples. Next, we will
recall how such operations naturally appear in  topology by considering
intersections of curves in surfaces, and sketch how this generalizes to
higher-dimensional manifolds. Finally, we will use Fox pairings to
construct some natural Poisson structures on the affine scheme of
representations of a cocommutative Hopf algebra in an arbitrary group
scheme.  (Based on joint works with Vladimir Turaev.)


Wakabayashi: A theory of dormant opers

A(n) (dormant) oper, being our central object of this talk, is a certain
principal homogeneous space on an algebraic curve (in positive
characteristic) equipped with an integrable connection. The study of
dormant opers and their moduli may be linked to various fields of
mathematics, e.g., the p-adic Teichmuller theory developed by Shinichi
Mochizuki, Gromov-Witten theory, combinatorics of rational polytopes (
and spin networks), etc. In this talk, we would like to introduce the
definition of a dormant oper and to present some related results,
including an explicit formula for the generic number of dormant opers,
which was conjectured by Kirti Joshi.


Papadopoulos: Spherical geometry II


Sato: On the cohomology ring of the handlebody mapping class group of genus
two

The genus two handlebody mapping class group acts on a tree constructed by
Kramer from the disk complex,
and decomposes into an amalgamated product of two subgroups.
We determine the integral cohomology ring of the genus two handlebody
mapping class group
by examining these subgroups and the Mayer-Vietoris exact sequence.
Using this result, we estimate the orders of low dimensional homology groups
of the genus three handlebody mapping class group.


Frenkel: Area formula for Hyperbolic Triangles and Lexell problem

My talk will be about an area formula in terms of side lengths for
triangles in plane hyperbolic geometry and its geometrical interpretation .
The proof of this formula is analogous to a proof given by Leonhard Euler
in the spherical case. I will speak in particular about the Lexell problem,
that is, the problem of finding the locus of vertices of triangle of fixed
area and fixed base.


Bao: Heegaard Floer homology for transverse graphs with sinks and sources

We defined the Heegaard Floer homology (HF) for balanced bipartite graphs.
Around the same time, Harvey and O’Donnol defined the combinatorial HF for
transverse graphs without sink and source (see the definition in
[arXiv:1506.04785v1]). In this talk, we compare these two methods and
consider the HF for transverse graphs with the same number of sinks and
sources in both analytic and combinatorial ways.


Watanabe: An invariant of fiberwise Morse functions on surface bundle over
S^1 by counting graphs

We apply Lescop’s construction of Z-equivariant perturbative invariant
of knots and 3-manifolds to the explicit equivariant propagator of
“Z-paths”.
We obtain an invariant of certain equivalence classes of fiberwise Morse
functions on a 3-manifold fibered over S^1, which can be
considered as a higher loop analogue of the Lefschetz zeta function and
whose
construction will be applied to that of finite type invariants of knots in
such
a 3-manifold.


Guichard: Compactifications of certain locally symmetric spaces
皆様、

以下のお知らせを送らせていただきます。よろしくお願い致します。

山田澄生

////////////////////////////////////////////////////////////////////////
メーリングリストの皆様、

重複ご海容ください。
日仏共同研究(タイヒミュラー空間と写像類群)による小研究集会を
11月16日(月)から20日(金)まで
東京大学大学院数理科学研究科 002 号室で
以下の要領で行います。使用言語は英語です。
皆様奮ってご参加ください。

とりいそぎ
大鹿健一(阪大理)
逆井卓也(東大数理)
河澄響矢(東大数理)

=========================
Atelier de travail franco-japonais sur la géométrie
des groupes modulaires et des espaces de Teichmüller

Les 16-20 novembre 2015
Salle 002, Faculté de sciences mathématiques, Université de Tokyo


Le lundi 16 novembre

(10:30-12:00  Salle 128
(Séminaire sur l'analyse géométrique complexe:
(Hideki Miyachi (Université d’Osaka)

13:30-14:30
Athanase Papadopoulos (Université de Strasbourg/CNRS)
Timelike geometry


Le mardi 17 novembre

10:00-11:00
Athanase Papadopoulos (Université de Strasbourg/CNRS)
Spherical geometry I

11:30-12:30
Takahito Naito (Université de Tokyo)
Sullivan's coproduct on the relative loop homology

14:00-15:00 + 15:30-16:30
Gwénaël Massuyeau (Université de Strasbourg/CNRS)
Fox pairings in Hopf algebras and Poisson structures

(16:30-17:00 Salle commune <premier étage>
(pause café pour Séminaire du mardi sur la topologie

(17:00-18:30 Salle 056
(Séminaire du mardi sur la topologie
(Atsuko Katanaga (Université de Shinshu)


Le mercredi 18 novembre

10:00-11:00
Athanase Papadopoulos (Université de Strasbourg/CNRS)
Spherical geometry II

11:30-12:30
Yasuo Wakabayashi (Université de Tokyo)
A theory of dormant opers

Le jeudi 19 novembre

10:00-11:00
Masatoshi Sato (Tokyo Denki University)
On the cohomology ring of the handlebody mapping class group of genus two

11:30-12:30
Elena Frenkel (Université de Strasbourg)
Area formula for Hyperbolic Triangles and Lexell problem

14:00-15:00
Yuanyuan Bao (Université de Tokyo)
Heegaard Floer homology for transverse graphs with sinks and sources

15:30-16:30
Tadayuki Watanabe (Université de Shimane)
An invariant of fiberwise Morse functions on surface bundle over S^1 by counting graphs

Le vendredi 20 novembre

09:30-10:30 + 11:00-12:00
Olivier Guichard (Université de Strasbourg)
Compactifications of certain locally symmetric spaces

(Les 20 à 22 novembre Salle 123
(Rigidity School, Tokyo 2015


=======
Résumés des exposés


Papadopoulos: Timelike geometry
Papadopoulos: Spherical geometry I


Naito: Sullivan's coproduct on the relative loop homology

Sullivan's coproduct is the coproduct on the relative homology of the
free loop space of a closed oriented manifold (called the relative loop
homology). It is known that the relative loop homology is an
infinitesimal bialgebra with respect to this coproduct and the loop
product. In this talk, we will give a homotopical description of
Sullivan's coproduct and introduce its properties. Moreover, we will
compute the coalgebra structure of spheres over the rational number
field by using the description.


Massuyeau: Fox pairings in Hopf algebras and Poisson structures

We will present the general theory of Fox pairings in Hopf algebras, which will be illustrated through several algebraic examples. Next, we will recall how such operations naturally appear in  topology by considering intersections of curves in surfaces, and sketch how this generalizes to higher-dimensional manifolds. Finally, we will use Fox pairings to construct some natural Poisson structures on the affine scheme of representations of a cocommutative Hopf algebra in an arbitrary group scheme.  (Based on joint works with Vladimir Turaev.)


Wakabayashi: A theory of dormant opers

A(n) (dormant) oper, being our central object of this talk, is a certain
principal homogeneous space on an algebraic curve (in positive
characteristic) equipped with an integrable connection. The study of
dormant opers and their moduli may be linked to various fields of
mathematics, e.g., the p-adic Teichmuller theory developed by Shinichi
Mochizuki, Gromov-Witten theory, combinatorics of rational polytopes (
and spin networks), etc. In this talk, we would like to introduce the
definition of a dormant oper and to present some related results,
including an explicit formula for the generic number of dormant opers,
which was conjectured by Kirti Joshi.


Papadopoulos: Spherical geometry II


Sato: On the cohomology ring of the handlebody mapping class group of genus two

The genus two handlebody mapping class group acts on a tree constructed by Kramer from the disk complex,
and decomposes into an amalgamated product of two subgroups.
We determine the integral cohomology ring of the genus two handlebody mapping class group
by examining these subgroups and the Mayer-Vietoris exact sequence.
Using this result, we estimate the orders of low dimensional homology groups
of the genus three handlebody mapping class group.


Frenkel: Area formula for Hyperbolic Triangles and Lexell problem

My talk will be about an area formula in terms of side lengths for triangles in plane hyperbolic geometry and its geometrical interpretation . The proof of this formula is analogous to a proof given by Leonhard Euler in the spherical case. I will speak in particular about the Lexell problem, that is, the problem of finding the locus of vertices of triangle of fixed area and fixed base.


Bao: Heegaard Floer homology for transverse graphs with sinks and sources

We defined the Heegaard Floer homology (HF) for balanced bipartite graphs. Around the same time, Harvey and O’Donnol defined the combinatorial HF for transverse graphs without sink and source (see the definition in [arXiv:1506.04785v1]). In this talk, we compare these two methods and consider the HF for transverse graphs with the same number of sinks and sources in both analytic and combinatorial ways.


Watanabe: An invariant of fiberwise Morse functions on surface bundle over S^1 by counting graphs

We apply Lescop’s construction of Z-equivariant perturbative invariant
of knots and 3-manifolds to the explicit equivariant propagator of “Z-paths”.
We obtain an invariant of certain equivalence classes of fiberwise Morse
functions on a 3-manifold fibered over S^1, which can be
considered as a higher loop analogue of the Lefschetz zeta function and whose
construction will be applied to that of finite type invariants of knots in such
a 3-manifold.


Guichard: Compactifications of certain locally symmetric spaces