English
Related papers

Related papers: Big mapping class groups and the co-Hopfian proper…

200 papers

We consider the homotopy type of maps between symplectic surface whose graphs form symplectic submanifolds of the product. We give a purely topological model for this space in terms of maps with constrained numbers of pre-images. We use…

Symplectic Geometry · Mathematics 2007-05-23 Joseph Coffey

Mann and Rafi's seminal work initiated the study of the coarse geometry of big mapping class groups. Specifically, they construct coarsely bounded (CB) generating sets for mapping class groups of a large class of infinite-type surfaces. In…

Geometric Topology · Mathematics 2025-05-23 Thomas Hill , Sanghoon Kwak , Rebecca Rechkin

Following the work of Rosendal and Mann and Rafi, we try to answer the following question: when is the mapping class group of an infinite-type surface quasi-isometric to a graph whose vertices are curves on that surface? With the assumption…

Geometric Topology · Mathematics 2022-08-08 Anschel Schaffer-Cohen

We define cusp-decomposable manifolds and prove smooth rigidity within this class of manifolds. These manifolds generally do not admit a nonpositively curved metric but can be decomposed into pieces that are diffeomorphic to finite volume,…

Geometric Topology · Mathematics 2011-10-19 T. Tam Nguyen Phan

We study the action of the mapping class group on the subspace of de Rham classes in the degree-two bounded cohomology of a hyperbolic surface. In particular, we show that the only fixed nontrivial finite-dimensional subspace is the one…

Geometric Topology · Mathematics 2024-10-30 Giuseppe Bargagnati , Federica Bertolotti , Pietro Capovilla , Francesco Milizia

We study the homeomorphism types of certain covers of (always orientable) surfaces, usually of infinite-type. We show that every surface with non-abelian fundamental group is covered by every noncompact surface, we identify the universal…

Geometric Topology · Mathematics 2025-08-05 Ian Biringer , Yassin Chandran , Tommaso Cremaschi , Jing Tao , Nicholas G. Vlamis , Mujie Wang , Brandis Whitfield

We give an alternate proof of the left-orderability of the mapping class group of a connected oriented infinite-type surface with a non-empty boundary. Our main strategy involves the inductive construction of a countable stable Alexander…

Geometric Topology · Mathematics 2024-08-13 Pravin Kumar , Apeksha Sanghi , Mahender Singh

We focus on two kinds of infinite index subgroups of the mapping class group of a surface associated with a Lagrangian submodule of the first homology of a surface. These subgroups, called Lagrangian mapping class groups, are known to play…

Geometric Topology · Mathematics 2012-03-28 Takuya Sakasai

We classify all $\pi_1$-injective proper maps between non-compact surfaces up to proper homotopy.

Geometric Topology · Mathematics 2025-07-15 Sumanta Das

A group is known as `large' if some finite index subgroup admits a surjective homomorphism onto a non-abelian free group. The main theorem of the paper is as follows. Let G be a finitely generated, large group and let g_1,...,g_r be a…

Group Theory · Mathematics 2007-05-23 Marc Lackenby

We classify up to conjugacy the group generated by a commuting pair of a periodic diffeomorphism and a hyperelliptic involution on an oriented closed surface. This result can be viewed as a refinement of Ishizaka's result on classification…

Geometric Topology · Mathematics 2020-01-01 Norihisa Takahashi , Hiraku Nozawa

Building on work of Farb and the second author, we prove that the group of automorphisms of the fine curve graph for a surface is isomorphic to the group of homeomorphisms of the surface. This theorem is analogous to the seminal result of…

Geometric Topology · Mathematics 2021-08-12 Adele Long , Dan Margalit , Anna Pham , Yvon Verberne , Claudia Yao

We show that every automorphism of the congruence completion of the extended mapping class group that preserves the set of conjugacy classes of procyclic groups generated by Dehn twists is inner, and that its automorphism group is naturally…

Geometric Topology · Mathematics 2026-01-09 Marco Boggi , Louis Funar

We introduce the notion of tight homomorphism into a locally compact group with nonvanishing bounded cohomology and study these homomorphisms in detail when the target is a Lie group of Hermitian type. Tight homomorphisms between Lie groups…

Differential Geometry · Mathematics 2008-09-15 Marc Burger , Alessandra Iozzi , Anna Wienhard

We investigate the injectivity of the Frobenius map on thickenings of smooth varieties in projective space over a field of positive characteristic. We obtain uniform bounds -- i.e., independent of the characteristic -- on the thickening…

Algebraic Geometry · Mathematics 2023-07-10 Bhargav Bhatt , Manuel Blickle , Gennady Lyubeznik , Anurag K. Singh , Wenliang Zhang

In this note, we establish a relationship between fractional Dehn twist coefficients of Riemann surface automorphisms and modular invariants of holomorphic families of algebraic curves. Specially, we give a characterization of…

Algebraic Geometry · Mathematics 2020-06-23 Xiao-Lei Liu

Following the philosophy of arithmetic topology, we describe a point of view which helps look at surfaces and $p$-adic fields in a "uniform way", and show that results on mapping class groups can be extended to this point of view, and thus…

Number Theory · Mathematics 2023-03-09 Nadav Gropper

We completely classify the locally finite, infinite graphs with pure mapping class groups admitting a coarsely bounded generating set. We also study algebraic properties of the pure mapping class group: We establish a semidirect product…

Group Theory · Mathematics 2025-08-06 George Domat , Hannah Hoganson , Sanghoon Kwak

We prove that the mapping class group of the one-holed Cantor tree surface is acyclic. This in turn determines the homology of the mapping class group of the once-punctured Cantor tree surface (i.e. the plane minus a Cantor set), in…

Geometric Topology · Mathematics 2025-01-07 Martin Palmer , Xiaolei Wu

Recently Bowden, Hensel and Webb defined the fine curve graph for surfaces, extending the notion of curve graphs for the study of homeomorphism or diffeomorphism groups of surfaces. Later Long, Margalit, Pham, Verberne and Yao proved that…

Geometric Topology · Mathematics 2024-12-25 Frédéric Le Roux , Maxime Wolff