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過去の記録 ～10/09｜次回の予定｜今後の予定 10/10～
| 開催情報 | 水曜日 16:30～18:00 数理科学研究科棟(駒場) 122号室 |
|---|---|
| 担当者 | 河東 泰之 |
| セミナーURL | https://www.ms.u-tokyo.ac.jp/~yasuyuki/tokyo-seminar.htm |
過去の記録
2010年07月15日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
小沢登高 氏 (東大数理)
Type II$_1$ von Neumann representations for Hecke operators on Maass forms (after F. Radulescu) (ENGLISH)
小沢登高 氏 (東大数理)
Type II$_1$ von Neumann representations for Hecke operators on Maass forms (after F. Radulescu) (ENGLISH)
2010年07月08日(木)
16:30-18:00 数理科学研究科棟(駒場) 122号室
Dave Penneys 氏 (UC Berkeley)
Killing weeds with annular multiplicities $*10$ via quadratic tangles (ENGLISH)
Dave Penneys 氏 (UC Berkeley)
Killing weeds with annular multiplicities $*10$ via quadratic tangles (ENGLISH)
[ 講演概要 ]
In recent work with Morrison, Peters, and Snyder, we eliminate two
families of possible principal graphs with graph norms less than 5 using
techniques derived from Jones' work on quadratic tangles.
In recent work with Morrison, Peters, and Snyder, we eliminate two
families of possible principal graphs with graph norms less than 5 using
techniques derived from Jones' work on quadratic tangles.
2010年07月06日(火)
16:30-18:00 数理科学研究科棟(駒場) 118号室
Robert Sims 氏 (Univ. Arizona)
On the Existence of the Dynamics for Anharmonic Quantum Oscillator Systems (ENGLISH)
Robert Sims 氏 (Univ. Arizona)
On the Existence of the Dynamics for Anharmonic Quantum Oscillator Systems (ENGLISH)
2010年06月24日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Thomas Sinclair 氏 (Vanderbilt Univ.)
Strong solidity of factors from lattices in SO(n,1) and SU(n,1) (ENGLISH)
Thomas Sinclair 氏 (Vanderbilt Univ.)
Strong solidity of factors from lattices in SO(n,1) and SU(n,1) (ENGLISH)
[ 講演概要 ]
Generalizing techniques found in Ozawa and Popa,
``On a class of II$_1$ factors with at most one Cartan subalgebra, II''
(Amer. J. Math., to appear), we show that the group factors of ICC
lattices in SO(n,1) and SU(n,1), $n\\ge2$, are strongly solid. If
time permits, we will also discuss applications to $L^2$-rigidity.
Generalizing techniques found in Ozawa and Popa,
``On a class of II$_1$ factors with at most one Cartan subalgebra, II''
(Amer. J. Math., to appear), we show that the group factors of ICC
lattices in SO(n,1) and SU(n,1), $n\\ge2$, are strongly solid. If
time permits, we will also discuss applications to $L^2$-rigidity.
2010年06月17日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Feng Xu 氏 (UC Riverside)
On a relative version of Wall's conjecture (ENGLISH)
Feng Xu 氏 (UC Riverside)
On a relative version of Wall's conjecture (ENGLISH)
2010年06月10日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Mikael Pichot 氏 (IPMU)
Random groups and nonarchimedean lattices (JAPANESE)
Mikael Pichot 氏 (IPMU)
Random groups and nonarchimedean lattices (JAPANESE)
2010年06月03日(木)
16:30-18:00 数理科学研究科棟(駒場) 122号室
山下真 氏 (東大数理)
Fixed Points in the Stone-Cech boundary of Groups (ENGLISH)
山下真 氏 (東大数理)
Fixed Points in the Stone-Cech boundary of Groups (ENGLISH)
[ 講演概要 ]
We discuss the class of discrete groups which admit fixed points under the adjoint action on the Stone-Cech boundary. Such groups have vanishing $L^2$-Betti numbers, and nonamenable ones fail to have property (AO).
We discuss the class of discrete groups which admit fixed points under the adjoint action on the Stone-Cech boundary. Such groups have vanishing $L^2$-Betti numbers, and nonamenable ones fail to have property (AO).
2010年05月27日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Catherine Oikonomides 氏 (東大数理)
The C*-algebra of codimension one foliations which are almost without holonomy (ENGLISH)
Catherine Oikonomides 氏 (東大数理)
The C*-algebra of codimension one foliations which are almost without holonomy (ENGLISH)
2010年05月06日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
山下 真 氏 (東大数理)
Connes-Landi Deformation of Spectral Triples (ENGLISH)
山下 真 氏 (東大数理)
Connes-Landi Deformation of Spectral Triples (ENGLISH)
[ 講演概要 ]
We describe a way to deform spectral triples with a 2-torus action and a real deformation parameter, motivated by deformation of manifolds after Connes-Landi. Such deformations are shown to have naturally isomorphic K-theoretic invariants independent of the deformation parameter.
We describe a way to deform spectral triples with a 2-torus action and a real deformation parameter, motivated by deformation of manifolds after Connes-Landi. Such deformations are shown to have naturally isomorphic K-theoretic invariants independent of the deformation parameter.
2010年04月22日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Nigel Higson 氏 (Pennsylvania State Univ.)
The Baum-Connes Conjecture and Group Representations (ENGLISH)
Nigel Higson 氏 (Pennsylvania State Univ.)
The Baum-Connes Conjecture and Group Representations (ENGLISH)
[ 講演概要 ]
The Baum-Connes conjecture asserts a sort of duality between the reduced unitary dual of a group and (a variant of) the classifying space of the group. The conjectured duality occurs at the level of K-theory. For example, for free abelian groups it amounts to a K-theoretic form of Fourier-Mukai duality. The conjecture has well-known applications in topology and geometry, but it also resonates in various ways with Lie groups and representation theory. I'll try to indicate how this comes about, and then focus on a fairly new aspect of the relationship that develops some early ideas of Mackey.
The Baum-Connes conjecture asserts a sort of duality between the reduced unitary dual of a group and (a variant of) the classifying space of the group. The conjectured duality occurs at the level of K-theory. For example, for free abelian groups it amounts to a K-theoretic form of Fourier-Mukai duality. The conjecture has well-known applications in topology and geometry, but it also resonates in various ways with Lie groups and representation theory. I'll try to indicate how this comes about, and then focus on a fairly new aspect of the relationship that develops some early ideas of Mackey.
2010年02月18日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Roberto Longo 氏 (University of Rome, Tor Vergata)
Von Neumann Algebras and Boundary Quantum Field Theory
Roberto Longo 氏 (University of Rome, Tor Vergata)
Von Neumann Algebras and Boundary Quantum Field Theory
2010年01月21日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
山下真 氏 (東大数理)
On Subfactors Arising from Asymptotic Representations of Symmetric Groups
山下真 氏 (東大数理)
On Subfactors Arising from Asymptotic Representations of Symmetric Groups
2010年01月19日(火)
16:30-18:00 数理科学研究科棟(駒場) 126号室
高井博司 氏 (首都大学東京)
Entire Cyclic Cohomology of Noncommutative Spheres
高井博司 氏 (首都大学東京)
Entire Cyclic Cohomology of Noncommutative Spheres
2010年01月14日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Marius Junge 氏 (Univ. Illinois, Urbana-Champaign)
Applications of operator algebras in Quantum information theory
Marius Junge 氏 (Univ. Illinois, Urbana-Champaign)
Applications of operator algebras in Quantum information theory
2010年01月07日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Luc Rey-Bellet 氏 (Univ. Massachusetts)
Large deviations, Billiards, and Non-equilibrium Statistical Mechanics
Luc Rey-Bellet 氏 (Univ. Massachusetts)
Large deviations, Billiards, and Non-equilibrium Statistical Mechanics
2009年12月22日(火)
14:40-18:00 数理科学研究科棟(駒場) 128号室
谷本溶 氏 (Univ. Roma ``Tor Vergata'') 14:40-16:10
Symmetric representations of the group of diffeomorphisms of $\\mathbb R$
David Kerr 氏 (Texas A&M Univ.) 16:30-18:00
Topological entropy for actions of sofic groups
谷本溶 氏 (Univ. Roma ``Tor Vergata'') 14:40-16:10
Symmetric representations of the group of diffeomorphisms of $\\mathbb R$
David Kerr 氏 (Texas A&M Univ.) 16:30-18:00
Topological entropy for actions of sofic groups
2009年12月17日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
佐藤康彦 氏 (北海道大理)
Almost commuting unitaries and ${\\mathbb{Z}}^2$-action
佐藤康彦 氏 (北海道大理)
Almost commuting unitaries and ${\\mathbb{Z}}^2$-action
2009年12月10日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
張欽 氏 (東大数理)
Symmetric norms and spaces of operators modelled on a semifinite von Neumann algebra
張欽 氏 (東大数理)
Symmetric norms and spaces of operators modelled on a semifinite von Neumann algebra
2009年12月03日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
見村万佐人 氏 (東大数理)
Vanishing of quasi-homomorphisms and the stable commutator
lengths on special linear groups over euclidean rings
見村万佐人 氏 (東大数理)
Vanishing of quasi-homomorphisms and the stable commutator
lengths on special linear groups over euclidean rings
2009年11月12日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
酒匂宏樹 氏 (東大数理)
Recent results for amalgamated free products of type II$_1$ factors
酒匂宏樹 氏 (東大数理)
Recent results for amalgamated free products of type II$_1$ factors
2009年10月29日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Robert Coquereaux 氏 (CNRS/CPT, Marseille)
Fusion graphs for Lie groups at level k and quantum symmetries
Robert Coquereaux 氏 (CNRS/CPT, Marseille)
Fusion graphs for Lie groups at level k and quantum symmetries
2009年10月22日(木)
16:30-18:00 数理科学研究科棟(駒場) 128号室
Adam Skalski 氏 (Lancaster University)
On some questions related to Voiculescu's noncommutative topological entropy
Adam Skalski 氏 (Lancaster University)
On some questions related to Voiculescu's noncommutative topological entropy
2009年09月07日(月)
17:00-18:30 数理科学研究科棟(駒場) 056号室
Marek Bozejko 氏 (University of Wroclaw)
Generalized Gaussian field, theta function of Jacobi and functor of second quantization
Marek Bozejko 氏 (University of Wroclaw)
Generalized Gaussian field, theta function of Jacobi and functor of second quantization
2009年07月23日(木)
16:30-18:00 数理科学研究科棟(駒場) 056号室
Catherine Oikonomides 氏 (慶応大理工)
Cyclic cohomology and the Novikov conjecture
Catherine Oikonomides 氏 (慶応大理工)
Cyclic cohomology and the Novikov conjecture
2009年07月16日(木)
16:30-18:00 数理科学研究科棟(駒場) 056号室
Ingo Runkel 氏 (King's College London)
Algebraic structures in conformal field theory
Ingo Runkel 氏 (King's College London)
Algebraic structures in conformal field theory
[ 講演概要 ]
It turned out to be fruitful to isolate questions in CFT which can be formulated in a purely categorical fashion. The way left and right moving degrees of freedom can be combined to a consistent theory is an example of this, the relevant structure being a commutative symmetric Frobenius algebra. This is true independently of whether CFT is formulated via sewing of surfaces or nets of operator algebras. Another example is modular invariance, which has a surprising alternative formulation as a certain maximality condition.
It turned out to be fruitful to isolate questions in CFT which can be formulated in a purely categorical fashion. The way left and right moving degrees of freedom can be combined to a consistent theory is an example of this, the relevant structure being a commutative symmetric Frobenius algebra. This is true independently of whether CFT is formulated via sewing of surfaces or nets of operator algebras. Another example is modular invariance, which has a surprising alternative formulation as a certain maximality condition.
