English
Related papers

Related papers: Positive toric fibrations

200 papers

We prove a conjecture of Artur Elezi in a generalized form suggested by Givental. Namely, our main result relates genus-0 Gromov--Witten invariants of a bundle space with such invariants of the base, provided that the fiber is a toric…

Algebraic Geometry · Mathematics 2009-01-12 Jeffrey Brown

A toric variety is called fibered if it can be represented as a total space of fibre bundle over toric base and with toric fiber. Fibered toric varieties form a special case of toric variety bundles. In this note we first give an…

Algebraic Geometry · Mathematics 2023-11-06 Askold Khovanskii , Leonid Monin

We present a condition for towers of fiber bundles which implies that the fundamental group of the total space has a nilpotent subgroup of finite index whose torsion is contained in its center. Moreover, the index of the subgroup can be…

Algebraic Topology · Mathematics 2018-10-04 Vitali Kapovitch , Anton Petrunin , Wilderich Tuschmann

We construct an I-function for toric bundles obtained as a fiberwise GIT quotient of a (not necessarily split) vector bundle. This is a generalization of Brown's I-function for split toric bundles and the I-function for non-split projective…

Algebraic Geometry · Mathematics 2024-06-25 Yuki Koto

The generalized Miller-Morita-Mumford classes of a manifold bundle with fiber $M$ depend only on the underlying $\tau_M$-fibration, meaning the family of vector bundles formed by the tangent bundles of the fibers. This motivates a closer…

Algebraic Topology · Mathematics 2020-12-23 Alexander Berglund

Consider a smooth effective action of a torus $\mathbb{T}^n$ on a connected $C^{\infty}$-manifold $M$ of dimension $m$. Then $n\leq m$. In this work we show that if $n<m$, then there exist a complete vector field $X$ on $M$ such that the…

Differential Geometry · Mathematics 2015-10-08 F. J. Turiel , A. Viruel

We construct noncommutative principal bundles deforming principal bundles with a Drinfeld twist (2-cocycle). If the twist is associated with the structure group then we have a deformation of the fibers. If the twist is associated with the…

Quantum Algebra · Mathematics 2017-06-27 Paolo Aschieri , Pierre Bieliavsky , Chiara Pagani , Alexander Schenkel

We associate a root system to a finite set in a free abelian group and prove that its irreducible subsystem is of type A, B or D. We apply this general result to a torus manifold, where a torus manifold is a $2n$-dimensional connected…

Geometric Topology · Mathematics 2017-10-31 Shintaro Kuroki , Mikiya Masuda

Let X be a smooth projective complex curve, and let M be the moduli space of stable Higgs bundles on X (with genus g>1), with rank n and fixed determinant \xi, with n and deg(\xi) coprime. Let X' and \xi' be another such curve and line…

Algebraic Geometry · Mathematics 2007-05-23 Indranil Biswas , Tomas L. Gomez

An action of a compact Lie group is called equivariantly formal, if the Leray--Serre spectral sequence of its Borel fibration degenerates at the E_2-term. This term is as prominent as it is restrictive. In this article, also motivated by…

Algebraic Topology · Mathematics 2019-12-17 Manuel Amann , Leopold Zoller

In this paper we study continuous bundles of C*-algebras which are non-commutative analogues of principal torus bundles. We show that all such bundles, although in general being very far away from being locally trivial bundles, are at least…

K-Theory and Homology · Mathematics 2014-02-26 Siegfried Echterhoff , Ryszard Nest , Herve Oyono-Oyono

In this paper, we develop the theory of singular hermitian metrics on vector bundles. As an application, we give a structure theorem of a projective manifold $X$ with pseudo-effective tangent bundle: $X$ admits a smooth fibration $X \to Y$…

Algebraic Geometry · Mathematics 2021-01-27 Genki Hosono , Masataka Iwai , Shin-ichi Matsumura

A Lie groupoid principal $\mbbX$ bundle is a surjective submersion $\pi\colon P\to M$ with an action of $\mathbb{X}$ on $P$ with certain additional conditions. This paper offers a suitable definition for the notion of a connection on such…

Differential Geometry · Mathematics 2025-04-22 Saikat Chatterjee , Naga Arjun S J

We define formal orbifolds over an algebraically closed field of arbitrary characteristic as curves together with some branch data. Their \'etale coverings and their fundamental groups are also defined. These fundamental group approximates…

Algebraic Geometry · Mathematics 2015-12-11 Manish Kumar , A. J. Parameswaran

Let $X$ be a differentiable manifold endowed with a transitive action $\alpha:A\times X\longrightarrow X$ of a Lie group $A$. Let $K$ be a Lie group. Under suitable technical assumptions, we give explicit classification theorems, in terms…

Differential Geometry · Mathematics 2013-11-19 Indranil Biswas , Andrei Teleman

We classify 1-dimensional connected dually flat manifolds $M$ that are toric in the sense of [Molitor, arXiv:2109.04839], and show that the corresponding torifications are complex space forms. Special emphasis is put on the case where M is…

Differential Geometry · Mathematics 2023-09-22 Danuzia Figueirêdo , Mathieu Molitor

Let X be a smooth projective curve of genus at least two over the complex numbers. A pair (E,\phi) over X consists of an algebraic vector bundle E over X and a holomorphic section \phi of E. There is a concept of stability for pairs which…

Algebraic Geometry · Mathematics 2015-05-13 Vicente Munoz

Let X be a smooth, complete, toric variety. We study those curves C in X that are contractible, in the sense that there exists an equivariant morphism with connected fibers, with source X, that contracts exactly the irreducible curves that…

Algebraic Geometry · Mathematics 2007-05-23 Cinzia Casagrande

Given a complex manifold $M$ equipped with a holomorphic action of a connected complex Lie group $G$, and a holomorphic principal $H$--bundle $E_H$ over $X$ equipped with a $G$--connection $h$, we investigate the connections on the…

Differential Geometry · Mathematics 2017-07-19 Indranil Biswas , Arjun Paul , Arideep Saha

Let X be a compact connected Riemann surface equipped with an anti-holomorphic involution \sigma. Let G be a connected complex reductive affine algebraic group, and let \sigma_G be a real form of G. We consider holomorphic principal…

Algebraic Geometry · Mathematics 2012-09-26 Indranil Biswas , Jacques Hurtubise