English
Related papers

Related papers: $2$-stratifold groups have solvable Word Problem

200 papers

In response to a question raised by Belolipetsky and the first author, we prove that for every finite group $G$ there are infinitely many isomorphism classes of compact complex hyperbolic $2$-manifolds with automorphism group isomorphic to…

Geometric Topology · Mathematics 2025-12-23 Alexander Lubotzky , Matthew Stover

We construct connected $2$-arc-transitive covers of the Petersen graph with non-solvable transformation groups, solving the long-standing problem for the existence of such covers.

Combinatorics · Mathematics 2025-07-22 Jiyong Chen , Cai Heng Li , Ci Xuan Wu , Yan Zhou Zhu

The genus spectrum of a finite group $G$ is the set of all $g\geq 2$ such that $G$ acts faithfully and orientation-preserving on a closed compact orientable surface of genus $g$. This article is an overview of some results relating the…

Group Theory · Mathematics 2013-09-04 Jürgen Müller , Siddhartha Sarkar

Multifraction reduction is a new approach to the word problem for Artin-Tits groups and, more generally, for the enveloping group of a monoid in which any two elements admit a greatest common divisor. This approach is based on a rewrite…

Group Theory · Mathematics 2017-02-01 Patrick Dehornoy

We prove that a connected 2-dimensional orbifold with finitely generated and infinite orbifold fundamental group is good. We also describe all the good 2-dimensional orbifolds with finite orbifold fundamental groups

Geometric Topology · Mathematics 2020-05-25 S K Roushon

This paper investigates the new notion of $2$-word-$\pi$-repre\-sentable graphs: the nodes of the graph correspond to the letters of the two words and there exists an edge between two nodes if the projections of any two letters of both…

Combinatorics · Mathematics 2026-05-27 Duncan Adamson , Amanita Dietz , Pamela Fleischmann , Annika Huch , Silas Cato Sacher

We consider word maps and word maps with constants on a simple algebraic group. We present results on the images of such maps, in particular, we prove a theorem on the dominance of general word maps with constants, which can be viewed as an…

Group Theory · Mathematics 2018-01-03 Nikolai Gordeev , Boris Kunyavskii , Eugene Plotkin

The NP-hard general factor problem asks, given a graph and for each vertex a list of integers, whether the graph has a spanning subgraph where each vertex has a degree that belongs to its assigned list. The problem remains NP-hard even if…

Data Structures and Algorithms · Computer Science 2015-03-19 Gregory Gutin , Eun Jung Kim , Arezou Soleimanfallah , Stefan Szeider , Anders Yeo

We argue that for a smooth surface S, considered as a ramified cover over the projective plane branched over a nodal-cuspidal curve B one could use the structure of the fundamental group of the complement of the branch curve to understand…

Algebraic Geometry · Mathematics 2011-06-29 Michael Friedman , Mina Teicher

The fundamental group of the Menger universal curve is uncountable and not free, although all of its finitely generated subgroups are free. It contains an isomorphic copy of the fundamental group of every one-dimensional separable metric…

Geometric Topology · Mathematics 2018-02-02 Hanspeter Fischer , Andreas Zastrow

Jae-Suk Park and the second-named author introduce the deformation problem of coisotropic submanifolds of a symplectic manifold as the study of Mauer-Cartan moduli problem of an $L_\infty$ algebra attached to the foliation de-Rham complex…

Symplectic Geometry · Mathematics 2026-03-03 Taesu Kim , Yong-Geun Oh

We prove that the inertia groups of all sufficiently-connected, high-dimensional $(2n)$-manifolds are trivial. This is a key step toward a general classification of manifolds in the metastable range. Specifically, for $m \gg 0$ and…

Geometric Topology · Mathematics 2022-04-14 Robert Burklund , Jeremy Hahn , Andrew Senger

We prove that, under a simple condition on the cohomology ring, every closed 4-manifold has mod 2 Seiberg-Witten simple type. This result shows that there exists a large class of topological 4-manifolds such that all smooth structures have…

Geometric Topology · Mathematics 2021-03-31 Tsuyoshi Kato , Nobuhiro Nakamura , Kouichi Yasui

Motivated by the question of which completely regular semigroups have context-free word problem, we show that for certain classes of languages $\mathfrak{C}$(including context-free), every completely regular semigroup that is a union of…

Group Theory · Mathematics 2020-03-31 Tara Brough

The topology of symplectic 4-manifolds is related to that of singular plane curves via the concept of branched covers. Thus, various classification problems concerning symplectic 4-manifolds can be reformulated as questions about singular…

Geometric Topology · Mathematics 2007-05-23 Denis Auroux

We show that the domino problem is undecidable on orbit graphs of non-deterministic substitutions which satisfy a technical property. As an application, we prove that the domino problem is undecidable for the fundamental group of any closed…

Group Theory · Mathematics 2020-05-07 Nathalie Aubrun , Sebastián Barbieri , Etienne Moutot

In this paper, an explicit classification result for certain 5-manifolds with fundamental group Z/2 is obtained. These manifolds include total spaces of circle bundles over simply-connected 4-manifolds.

Geometric Topology · Mathematics 2011-06-14 Ian Hambleton , Yang Su

We begin with a review of the notion of a braid group. We then discuss some known solutions to decision problems in braid groups. We then move on to proving new results in braid group algorithmics. We offer a quick solution to the…

Group Theory · Mathematics 2007-05-23 Elie Feder

Let $G$ be a finite group and $H$ a core-free subgroup of $G$. We will show that if there exists a solvable, generating transversal of $H$ in $G$, then $G$ is a solvable group. Further, if $S$ is a generating transversal of $H$ in $G$ and…

Group Theory · Mathematics 2019-05-21 Vivek Kumar Jain

The orbifold braid groups of two dimensional orbifolds were defined in [1] (arXiv:math/9907194) to understand certain Artin groups as subgroups of some suitable orbifold braid groups. We studied orbifold braid groups in some more detail in…

Group Theory · Mathematics 2023-09-08 S. K. Roushon