English
Related papers

Related papers: Orderable groups and bundles

200 papers

We prove that the order of an ordered group is an interval order if and only if it is a semiorder. Next, we prove that every semiorder is isomorphic to a collection $\mathcal J$ of intervals of some totally ordered abelian group, these…

Combinatorics · Mathematics 2018-04-19 Maurice Pouzet , Imed Zaguia

The theory of principal bundles makes sense in any infinity-topos, such as that of topological, of smooth, or of otherwise geometric infinity-groupoids/infinity-stacks, and more generally in slices of these. It provides a natural geometric…

Algebraic Topology · Mathematics 2023-07-03 Thomas Nikolaus , Urs Schreiber , Danny Stevenson

This paper aims to introduce a more general definition of quasirandom groups and generalize several well-known results in the literature in this new setting. More precisely, let $G$ be a semi-direct product of groups and $X\subseteq G$, we…

Combinatorics · Mathematics 2023-08-28 Thang Pham , Boqing Xue

Results of Perron and Rolfsen imply that untwisted hyperbolic once-punctured torus bundles over the circle have bi-orderable fundamental groups. They do this by showing that the action of the monodromy preserves a "standard" bi-ordering…

Geometric Topology · Mathematics 2023-10-24 Jonathan Johnson , Henry Segerman

We define a total order, which we call rooted order, on minimal generating set of $J(P_n)^s$ where $J(P_n)$ is the cover ideal of a path graph on $n$ vertices. We show that each power of a cover ideal of a path has linear quotients with…

Commutative Algebra · Mathematics 2022-12-13 Nursel Erey

Continuous frames over a Hilbert space have a rich and sophisticated structure that can be represented in the form of a fiber bundle. The fiber bundle structure reveals the central importance of Parseval frames and the extent to which…

Functional Analysis · Mathematics 2015-12-15 Devanshu Agrawal , Jeff Knisley

In this paper, we elaborate ring theoretic properties of nodal orders. In particular, we prove that they are closed under taking crossed products with finite groups.

Representation Theory · Mathematics 2024-06-05 Igor Burban , Yuriy Drozd

Manifolds and fiber bundles, while superficially different, have strong parallels; in particular, they are both defined in terms of equivalence classes of atlases or in terms of maximal atlases, with the atlases treated as mere adjuncts.…

Algebraic Topology · Mathematics 2019-06-28 Seymour J. Metz

A principal toric bundle $M$ is a complex manifold equipped with a free holomorphic action of a compact complex torus $T$. Such a manifold is fibered over $M/T$, with fiber $T$. We discuss the notion of positivity in fiber bundles and…

Algebraic Geometry · Mathematics 2014-02-26 Misha Verbitsky

Infinitary operations, such as products indexed by countably infinite linear orders, arise naturally in the context of fundamental groups and groupoids. Despite the fact that the usual binary operation of the fundamental group determines…

Algebraic Topology · Mathematics 2020-04-14 Jeremy Brazas

In his $1994$ survey, Kleinert defined formally and formulated the problem to obtain unit theorems for unit groups of orders in a semisimple algebra $A$. If $A$ is a group algebra $FG$, it boils down to classifying all finite groups $G$…

Group Theory · Mathematics 2025-10-22 Geoffrey Janssens

We identify a class of linearly ordered topological spaces $X$ that may satisfy the property that $X\times X$ is homeomorphic to $X\times_l X$ or can be embedded into a linearly ordered space with the stated property. We justify the…

General Topology · Mathematics 2018-01-08 Raushan Buzyakova

Let G be an abelian group acting on a set X, and suppose that no element of G has any finite orbit of size greater than one. We show that every partial order on X invariant under $G$ extends to a linear order on X also invariant under G. We…

Group Theory · Mathematics 2013-09-30 Alexander R. Pruss

In this paper, we view the equivariant orientation theory of equivariant vector bundles from the lenses of equivariant Picard spectra. This viewpoint allows us to identify, for a finite group $\mathrm{G}$, a precise condition under which an…

Algebraic Topology · Mathematics 2024-09-24 Prasit Bhattacharya , Foling Zou

This paper provides a bridge between two active areas of research, the spectrum (set of element orders) and the power graph of a finite group. The order sequence of a finite group $G$ is the list of orders of elements of the group, arranged…

Group Theory · Mathematics 2025-10-22 Peter J. Cameron , Hiranya Kishore Dey

We completely characterize definable linear orders in o-minimal structures expanding groups. For example, let (P,<_p) be a linear order definable in the real field R. Then (P,<_p) embeds definably in (R^{n+1},<_l), where <_l is the…

Logic · Mathematics 2010-11-09 Janak Ramakrishnan

Let $X$ be any rational surface. We construct a tilting bundle $T$ on $X$. Moreover, we can choose $T$ in such way that its endomorphism algebra is quasi-hereditary. In particular, the bounded derived category of coherent sheaves on $X$ is…

Algebraic Geometry · Mathematics 2017-06-27 Lutz Hille , Markus Perling

An order-theoretic forest is a countable partial order such that the set of elements larger than any element is linearly ordered. It is an order-theoretic tree if any two elements have an upper-bound. The order type of a branch can be any…

Logic in Computer Science · Computer Science 2023-06-22 Bruno Courcelle

Let $G$ be a finite group. A sequence over $G$ means a finite sequence of terms from $G$, where repetition is allowed and the order is disregarded. A product-one sequence is a sequence whose elements can be ordered such that their product…

Number Theory · Mathematics 2020-11-17 Alfred Geroldinger , David J. Grynkiewicz , Jun Seok Oh , Qinghai Zhong

Let $k$ be a field of characteristic $0$, $X$ be a geometrically connected, smooth and proper variety over $k$ and $x\in X(k)$ be a base point. Using the notion of iterated universal extensions, we show that Nori's fundamental group…

Algebraic Geometry · Mathematics 2026-05-12 Xiaodong Yi