English
Related papers

Related papers: Torelli buildings and their automorphisms

200 papers

Let $S$ be a nonorientable surface of genus $g\ge 5$ with $n\ge 0$ punctures, and $\Mcg(S)$ its mapping class group. We define the complexity of $S$ to be the maximum rank of a free abelian subgroup of $\Mcg(S)$. Suppose that $S_1$ and…

Geometric Topology · Mathematics 2017-01-03 Ferihe Atalan , Błażej Szepietowski

The group of 2-by-2 matrices with integer entries and determinant $\pm > 1$ can be identified either with the group of outer automorphisms of a rank two free group or with the group of isotopy classes of homeomorphisms of a 2-dimensional…

Group Theory · Mathematics 2007-05-23 Martin R Bridson , Karen Vogtmann

Using the recently developed theory of finite type invariants of integral homology 3-spheres we study the structure of the Torelli group of a closed surface. Explicitly, we construct (a) natural cocycles of the Torelli group (with…

q-alg · Mathematics 2008-02-03 Stavros Garoufalidis , Jerome Levine

The Torelli group of a manifold is the group of all diffeomorphisms which act as the identity on the homology of the manifold. In this paper, we calculate the invariant part (invariant under the action of the automorphisms of the homology)…

Algebraic Topology · Mathematics 2017-05-17 Johannes Ebert , Oscar Randal-Williams

This article initiates a geometric study of the automorphism groups of general graph products of groups, and investigates the algebraic and geometric structure of automorphism groups of cyclic product of groups. For a cyclic product of at…

Group Theory · Mathematics 2018-03-21 Anthony Genevois , Alexandre Martin

We describe an underlying right angled building structure of any graph product of buildings. We describe the automorphism group of the graph product of buildings. We show that the notion of generalized graph product of a collection of…

Group Theory · Mathematics 2014-07-18 Aliska Gibbins

This paper is the first part in a 2 part study of an elementary functorial construction from the category of finite non-abelian groups to a category of singular compact, oriented 2-manifolds. After a desingularization process this…

Geometric Topology · Mathematics 2013-10-16 Mark Herman , Jonathan Pakianathan , Ergun Yalcin

An automorphism of a spherical building is called \textit{domestic} if it maps no chamber onto an opposite chamber. This paper forms a significant part of a large project classifying domestic automorphisms of spherical buildings of…

Group Theory · Mathematics 2024-02-08 Yannick Neyt , James Parkinson , Hendrik Van Maldeghem , Magali Victoor

An automorphism of a spherical building is called \textit{domestic} if it maps no chamber to an opposite chamber. In previous work the classification of domestic automorphisms in large spherical buildings of types $\mathsf{F}_4$,…

Group Theory · Mathematics 2025-04-22 James Parkinson , Hendrik Van Maldeghem

We study the arc complex of a surface with marked points in the interior and on the boundary. We prove that the isomorphism type of the arc complex determines the topology of the underlying surface, and that in all but a few cases every…

Geometric Topology · Mathematics 2015-06-01 Valentina Disarlo

This is an expository paper giving a proof of the existence and uniqueness of smooth structures (hence also PL structures) on topological surfaces. Most published proofs rely on the topological Schoenflies theorem, but here we use instead…

Geometric Topology · Mathematics 2025-02-14 Allen Hatcher

Trinomial hypersurfaces form a natural class of affine algebraic varieties closely connected with varieties admitting a torus action of complexity one. We investigate orbits of the automorphism group on these hypersurfaces. We prove that…

Algebraic Geometry · Mathematics 2022-05-06 Sergey Gaifullin , Georgiy Shirinkin

We offer a criterion for showing that the automorphism group of an ultrahomogeneous structure is topologically 2-generated and even has a cyclically dense conjugacy class. We then show how finite topological rank of the automorphism group…

Group Theory · Mathematics 2019-08-26 Itay Kaplan , Pierre Simon

We show that the group of type-preserving automorphisms of any irreducible semi-regular thick right-angled building is abstractly simple. When the building is locally finite, this gives a large family of compactly generated (abstractly)…

Group Theory · Mathematics 2014-05-15 Pierre-Emmanuel Caprace

We prove that each injective simplicial map from the arc complex of a compact, connected, nonorientable surface with nonempty boundary to itself is induced by a homeomorphism of the surface. We also prove that the automorphism group of the…

Geometric Topology · Mathematics 2014-10-01 Elmas Irmak

Examples of aspherical closed symplectic 4-manifolds are presented whose Sullivan minimal models are (1,n)-formal for any n, without being formal. They have as cohomology algebra, signature, canonical class, those of a product of a closed…

Symplectic Geometry · Mathematics 2024-01-17 Jaume Amorós

We study the groups of automorphisms of rational algebraic surfaces that admit a relatively minimal pencil of curves of arithmetic genus one over an algebraically closed field of arbitrary characteristic. In particular, we classify such…

Algebraic Geometry · Mathematics 2021-06-25 Igor Dolgachev , Gebhard Martin

We show that every automorphism of a thick twin building interchanging the halves of the building maps some residue to an opposite one. Furthermore we show that no automorphism of a locally finite 2-spherical twin building of rank at least…

Combinatorics · Mathematics 2012-03-29 Alice Devillers , James Parkinson , Hendrik Van Maldeghem

In this paper, we show that the infinitesimal Torelli theorem implies the existence of deformations of automorphisms. In the first part, we use Hodge theory and deformation theory to study the deformations of automorphisms of complex…

Algebraic Geometry · Mathematics 2017-03-24 Xuanyu Pan

We classify compact 2-connected homogeneous spaces with the same rational cohomology as a product of spheres. This classification relies on spectral sequences, homotopy theory, and representation theory. We then apply this classification to…

Geometric Topology · Mathematics 2007-05-23 Linus Kramer