English
Related papers

Related papers: Loop groups and twin buildings

200 papers

We define a compactification of an affine building $\I$ indexed by a family of partitions of the director space $\vec A$ of one of its appartments $A$. This compactification is similar to Satake's compatification of a symetric space, and it…

Group Theory · Mathematics 2009-03-04 Cyril Charignon

For an almost split Kac-Moody group G over a local non-archimedean field, the last two authors constructed a spherical Hecke algebra H (over the complex numbers C, say) and its Satake isomorphism with the commutative algebra of Weyl…

Representation Theory · Mathematics 2019-02-20 Nicole Bardy-Panse , Stéphane Gaussent , Guy Rousseau

Positive configurations of points in the affine building were introduced in \cite{Le} as the basic object needed to define higher laminations. We start by giving a self-contained, elementary definition of positive configurations of points…

Representation Theory · Mathematics 2015-11-03 Ian Le , Evan O'Dorney

We give a Thurston-like definition for laminations on higher Teichmuller spaces associated to a surface $S$ and a semi-simple group $G$ for $G-SL_m$ and $PGL_m$. The case $G=SL_2$ or $PGL_2$ corresponds to the classical theory of…

Representation Theory · Mathematics 2016-07-20 Ian Le

We prove a purely topological characterization of the Moufang property for disconnected compact polygons in terms of convergence groups. As a consequence, we recover the fact that a locally finite thick affine building of rank 3 is a…

Group Theory · Mathematics 2016-12-14 Nicolas Radu

This text provides an introduction and complements to some basic constructions and results in 2-representation theory of Kac-Moody algebras.

Representation Theory · Mathematics 2011-12-16 Raphael Rouquier

We construct the finite-dimensional continuous complex representations of $\mathrm{SL}_2$ over compact discrete valuation rings of even residual characteristic. We also prove that the complex group algebras of $\mathrm{SL}_2$ over finite…

Representation Theory · Mathematics 2023-08-17 M Hassain

We give a realization of the infinity crystal for affine sl(2) using decorated polygons. The construction and proof are combinatorial, making use of Kashiwara and Saito's characterization of the infinity crystal in terms of the *…

Combinatorics · Mathematics 2012-03-01 Pierre Baumann , Thomas Dunlap , Joel Kamnitzer , Peter Tingley

We geometrically characterise the Veronese representations of ring projective planes over algebras which are analogues of the dual numbers, giving rise to projective Hjelmslev planes of level 2 coordinatised over quadratic alternative…

Combinatorics · Mathematics 2020-01-14 Anneleen De Schepper , Hendrik Van Maldeghem

Let $G$ be a matrix group. Topological $G$-manifolds with Palais-proper action have the $G$-homotopy type of countable $G$-CW complexes (3.2). This generalizes E Elfving's dissertation theorem for locally linear $G$-manifolds (1996). Also…

Geometric Topology · Mathematics 2021-01-05 Qayum Khan

This is an announcement of some of the results obtained as a part of the second author's Ph.D. thesis. In the first part, we prove that the fundamental group of an acylindrical complex of hyperbolic groups with finite edge groups is…

Group Theory · Mathematics 2021-07-13 Pranab Sardar , Ravi Tomar

$p$-Adic compactifications of geometric loop and diffeomorphism groups of compact manifolds on finite-dimensional spaces over non-Archimedean fields are investigated. Weakened topology is introduced. The structure of newly constructed…

Group Theory · Mathematics 2007-05-23 S. Ludkovsky , B. Diarra

Starting with a highest weight representation of a Kac-Moody group over the complex numbers, we construct a monoid whose unit group is the image of the Kac-Moody group under the representation, multiplied by the nonzero complex numbers. We…

Representation Theory · Mathematics 2016-07-11 Zhenheng Li , Zhuo Li , Claus Mokler

Starting with a highest weight representation of a Kac-Moody group over the complex numbers, we construct a monoid whose unit group is the image of the Kac-Moody group under the representation, multiplied by the nonzero complex numbers. We…

Representation Theory · Mathematics 2016-11-09 Zhenheng Li , Zhuo Li , Claus Mokler

A lot of developments made during the last years show that Kac-Moody algebras play an important role in the algebraic structure of some supergravity theories. These algebras would generate infinite-dimensional symmetry groups. The possible…

High Energy Physics - Theory · Physics 2009-10-09 Nassiba Tabti

Firstly, we prove that every closed subgroup $H$ of type-preserving automorphisms of a locally finite thick affine building $\Delta$ of dimension $\geq 2$ that acts strongly transitively on $\Delta$ is Moufang. If moreover $\Delta$ is…

Group Theory · Mathematics 2021-10-11 Corina Ciobotaru

We develop the basic topological properties of compact polygons, i.e. of compact topological Tits buildings of rank two. It is proved that the Coxeter diagram of such a building is always crystallographic, that is, compact connected n-gons…

Differential Geometry · Mathematics 2007-05-23 Linus Kramer

We construct rank 2 thick nondiscrete affine buildings associated with an arbitrary finite dihedral group.

Metric Geometry · Mathematics 2008-09-02 Arkady Berenstein , Michael Kapovich

We consider the subalgebras of split real, non-twisted affine Kac-Moody Lie algebras that are fixed by the Chevalley involution. These infinite-dimensional Lie algebras are not of Kac-Moody type and admit finite-dimensional unfaithful…

Representation Theory · Mathematics 2022-03-30 Axel Kleinschmidt , Ralf Köhl , Robin Lautenbacher , Hermann Nicolai

This is the third paper of a series relating the equivariant twisted $K$-theory of a compact Lie group $G$ to the ``Verlinde space'' of isomorphism classes of projective lowest-weight representations of the loop groups. Here, we treat…

Algebraic Topology · Mathematics 2007-05-23 Daniel S. Freed , Michael J. Hopkins , Constantin Teleman