Equivariant Analytic Localization of Group Representations

Equivariant Analytic Localization of Group Representations
Author: Laura Ann Smithies
Publisher: American Mathematical Soc.
Total Pages: 106
Release: 2001
Genre: Mathematics
ISBN: 0821827251

This book is intended for graduate students and research mathematicians interested in topological groups, Lie groups, category theory, and homological algebra.

Homotopy Theory of Diagrams

Homotopy Theory of Diagrams
Author: Wojciech Chachólski
Publisher: American Mathematical Soc.
Total Pages: 106
Release: 2002
Genre: Mathematics
ISBN: 0821827596

In this paper the authors develop homotopy theoretical methods for studying diagrams. In particular they explain how to construct homotopy colimits and limits in an arbitrary model category. The key concept introduced is that of a model approximation. A model approximation of a category $\mathcal{C}$ with a given class of weak equivalences is a model category $\mathcal{M}$ together with a pair of adjoint functors $\mathcal{M} \rightleftarrows \mathcal{C}$ which satisfy certain properties. The key result says that if $\mathcal{C}$ admits a model approximation then so does the functor category $Fun(I, \mathcal{C})$.

Blowing Up of Non-Commutative Smooth Surfaces

Blowing Up of Non-Commutative Smooth Surfaces
Author: M. van den Bergh
Publisher: American Mathematical Soc.
Total Pages: 157
Release: 2001
Genre: Mathematics
ISBN: 0821827545

This book is intended for graduate students and research mathematicians interested in associative rings and algebras, and noncommutative geometry.

Extending Intersection Homology Type Invariants to Non-Witt Spaces

Extending Intersection Homology Type Invariants to Non-Witt Spaces
Author: Markus Banagl
Publisher: American Mathematical Soc.
Total Pages: 101
Release: 2002
Genre: Mathematics
ISBN: 0821829882

Intersection homology theory provides a way to obtain generalized Poincare duality, as well as a signature and characteristic classes, for singular spaces. For this to work, one has had to assume however that the space satisfies the so-called Witt condition. We extend this approach to constructing invariants to spaces more general than Witt spaces.

Kac Algebras Arising from Composition of Subfactors: General Theory and Classification

Kac Algebras Arising from Composition of Subfactors: General Theory and Classification
Author: Masaki Izumi
Publisher: American Mathematical Soc.
Total Pages: 215
Release: 2002
Genre: Mathematics
ISBN: 0821829351

This title deals with a map $\alpha$ from a finite group $G$ into the automorphism group $Aut({\mathcal L})$ of a factor ${\mathcal L}$ satisfying (i) $G=N \rtimes H$ is a semi-direct product, (ii) the induced map $g \in G \to [\alpha_g] \in Out({\mathcal L})=Aut({\mathcal L})/Int({\mathcal L})$ is an injective homomorphism, and (iii) the restrictions $\alpha \! \! \mid_N, \alpha \! \! \mid_H$ are genuine actions of the subgroups on the factor ${\mathcal L}$. The pair ${\mathcal M}={\mathcal L} \rtimes_{\alpha} H \supseteq {\mathcal N}={\mathcal L} DEGREES{\alpha\mid_N}$ (of the crossed product ${\mathcal L} \rtimes_{\alpha} H$ and the fixed-point algebra ${\mathcal L} DEGREES{\alpha\mid_N}$) gives an irreducible inclusion of factors with Jones index $\# G$. The inclusion ${\mathcal M} \supseteq {\mathcal N}$ is of depth $2$ and hence known to correspond to a Kac algebra of dim

Desingularization of Nilpotent Singularities in Families of Planar Vector Fields

Desingularization of Nilpotent Singularities in Families of Planar Vector Fields
Author: Daniel Panazzolo
Publisher: American Mathematical Soc.
Total Pages: 122
Release: 2002
Genre: Mathematics
ISBN: 0821829270

This work aims to prove a desingularization theorem for analytic families of two-dimensional vector fields, under the hypothesis that all its singularities have a non-vanishing first jet. Application to problems of singular perturbations and finite cyclicity are discussed in the last chapter.

Lie Algebras Graded by the Root Systems BC$_r$, $r\geq 2$

Lie Algebras Graded by the Root Systems BC$_r$, $r\geq 2$
Author: Bruce Normansell Allison
Publisher: American Mathematical Soc.
Total Pages: 175
Release: 2002
Genre: Mathematics
ISBN: 0821828118

Introduction The $\mathfrak{g}$-module decomposition of a $\mathrm{BC}_r$-graded Lie algebra, $r\ge 3$ (excluding type $\mathrm{D}_3)$ Models for $\mathrm{BC}_r$-graded Lie algebras, $r\ge 3$ (excluding type $\mathrm{D}_3)$ The $\mathfrak{g}$-module decomposition of a $\mathrm{BC}_r$-graded Lie algebra with grading subalgebra of type $\mathrm{B}_2$, $\mathrm{C}_2$, $\mathrm{D}_2$, or $\mathrm{D}_3$ Central extensions, derivations and invariant forms Models of $\mathrm{BC}_r$-graded Lie algebras with grading subalgebra of type $\mathrm{B}_2$, $\mathrm{C}_2$, $\mathrm{D}_2$, or $\mathrm{D}_3$ Appendix: Peirce decompositions in structurable algebras References.

Homogeneous Spaces, Tits Buildings, and Isoparametric Hypersurfaces

Homogeneous Spaces, Tits Buildings, and Isoparametric Hypersurfaces
Author: Linus Kramer
Publisher: American Mathematical Soc.
Total Pages: 137
Release: 2002
Genre: Mathematics
ISBN: 0821829068

This title classifys 1-connected compact homogeneous spaces which have the same rational cohomology as a product of spheres $\mahtbb{S} DEGREES{n_1}\times\mathbb{S} DEGREES{n_2}$, with $3\leq n_1\leq n_2$ and $n_2$ odd. As an application, it classifys compact generalized quadrangles (buildings of type $C_2)$ which admit a point transitive automorphism group, and isoparametric hypersurfaces which admit a transitive isometry group on one f