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Related papers: Good, but not very good orbifolds

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We construct a function for almost-complex Riemannian manifolds. Non-vanishing of the function for the almost-complex structure implies the almost-complex structure is not integrable. Therefore the constructed function is an obstruction for…

General Mathematics · Mathematics 2019-03-11 Jun Ling

Let A be a finitely generated associative algebra over an algebraically closed field. We characterize the finite dimensional modules over A whose orbit closures are regular varieties.

Algebraic Geometry · Mathematics 2007-05-23 Nguyen Quang Loc , Grzegorz Zwara

In this paper we study three-dimensional orbifolds by 2-groups with a trivially-acting one-form symmetry group BK. These orbifolds have a global two-form symmetry, and so one expects that they decompose into (are equivalent to) a disjoint…

High Energy Physics - Theory · Physics 2022-09-07 T. Pantev , D. Robbins , E. Sharpe , T. Vandermeulen

We study the possibility of realizing exotic smooth structures on punctured simply connected $4$-manifolds as leaves of a codimension one foliation on a compact manifold. In particular, we show the existence of uncountably many smooth open…

Geometric Topology · Mathematics 2018-06-13 Carlos Meniño Cotón , Paul A. Schweitzer

We give an example of a projective manifold with dense entire curves such that every Brody curve is degenerate.

Complex Variables · Mathematics 2007-05-23 Joerg Winkelmann

We construct examples of simply connected nonalgebraic symplectic fourfolds with a prescribed number of nonintersecting symplectic curves with positive self-intersections.

Algebraic Geometry · Mathematics 2007-05-23 Fedor Bogomolov , Yuri Tschinkel

We construct complete, finite volume, 4-dimensional manifolds with sectional curvature $-1<K<0$ with cusp cross sections compact solvmanifolds.

Differential Geometry · Mathematics 2012-07-10 T. Tam Nguyen Phan

If $f$ is an automorphism of a compact simply connected K\"ahler manifold with trivial canonical bundle that fixes a K\"ahler class, then the order of $f$ is finite. We apply this well known result to construct compact non-K\"ahler…

Algebraic Geometry · Mathematics 2012-11-30 Gunnar Þór Magnússon

We provide an alternative, simpler proof of the existence of thick triangulations for noncompact $\mathcal{C}^1$ manifolds. Moreover, this proof is simpler than the original one given in \cite{pe}, since it mainly uses tools of elementary…

Geometric Topology · Mathematics 2010-05-12 Emil Saucan , Meir Katchalski

We explicitly construct small triangulations for a number of well-known 3-dimensional manifolds and give a brief outline of some aspects of the underlying theory of 3-manifolds and its historical development.

Geometric Topology · Mathematics 2007-05-23 Frank H. Lutz

Results are well-known

Combinatorics · Mathematics 2010-03-17 Mark Pankov

We investigate the curvature of invariant metrics on G-manifolds with finitely many non-principal orbits. We prove existence results for metrics of positive Ricci curvature and non-negative sectional curvature, and discuss some families of…

Differential Geometry · Mathematics 2011-07-26 Stefan Bechtluft-Sachs , David J. Wraith

We discuss an example related to the method of Brody. The example is an open subset of a compact complex torus which is covered by entire curves, but not by Brody curves.

Complex Variables · Mathematics 2007-05-23 Joerg Winkelmann

Orbifold compactifications with continuous Wilson lines have very interesting characteristics and as a consequence they are candidates to obtain realistic models. We perform an analysis of the soft supersymmetry-breaking terms arising in…

High Energy Physics - Phenomenology · Physics 2014-11-17 Hang Bae Kim , Carlos Munoz

The class of Riemannian orbifolds of dimension n defined by a lower bound on the sectional curvature and the volume and an upper bound on the diameter has only finitely many members up to orbifold homeomorphism. Furthermore, any class of…

Differential Geometry · Mathematics 2020-01-23 John Harvey

We exhibit a 3-manifold which admits no tight contact structure.

Geometric Topology · Mathematics 2007-05-23 John B. Etnyre , Ko Honda

This paper introduces a notion of decompositions of integral varifolds into countably many integral varifolds, and the existence of such decomposition of integral varifolds whose first variation is representable by integration is…

Differential Geometry · Mathematics 2023-07-26 Hsin-Chuang Chou

We show that an oriented elliptic 3-manifold admits a universally tight positive contact structure iff the corresponding group of deck transformations on $S^3$ preserves a standard contact structure pointwise. We also relate univerally…

Geometric Topology · Mathematics 2007-05-23 Siddhartha Gadgil

We define orbifold mapping class groups (with marked points) and study them using their action on certain orbifold analogs of arcs and simple closed curves. Moreover, we establish a Birman exact sequence for suitable subgroups of orbifold…

Geometric Topology · Mathematics 2023-05-09 Jonas Flechsig

We exhibit a family of metrizable manifolds such that any finite group appears as the fundamental group of one of them. These spaces are especially interesting as they can be easily visualized, as opposed to classical examples of spaces…

Algebraic Topology · Mathematics 2024-11-12 Luca Tanganelli Castrillón