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Non-split almost complex supermanifolds and non-split Riemannian supermanifolds are studied. The first obstacle for a splitting is parametrized by group orbits on an infinite dimensional vector space. Further it is shown that non-split…

Differential Geometry · Mathematics 2015-01-29 Matthias Kalus

In this paper, we classify the characteristic matrices associated to quasitoric manifolds over a vertex cut of a finite product of simplices. We discuss the integral cohomology rings of these quasitoric manifolds with possibly minimal…

Algebraic Topology · Mathematics 2022-12-26 Soumen Sarkar , Subhankar Sau

Relying on rays, we search for submodules of a module V over a supertropical semiring on which a given anisotropic quadratic form is quasilinear. Rays are classes of a certain equivalence relation on V, that carry a notion of convexity,…

Rings and Algebras · Mathematics 2018-07-10 Zur Izhakian , Manfred Knebusch

We prove a Painlev\'e theorem for bounded quasiregular curves in Euclidean spaces extending removability results for quasiregular mappings due to Iwaniec and Martin. The theorem is proved by extending a fundamental inequality for volume…

Differential Geometry · Mathematics 2024-12-20 Toni Ikonen

Given a closed orientable Euclidean cone 3-manifold C with cone angles less than or equal to pi, and which is not almost product, we describe the space of constant curvature cone structures on C with cone angles less than pi. We establish a…

Geometric Topology · Mathematics 2014-11-11 Joan Porti , Hartmut Weiss

This research work introduces the structure of invariant and screen semi-invariant lightlike submanifolds of a metallic semi-Riemannian manifold with a quarter symmetric non-metric connection, elaborated with examples. It delves into the…

Differential Geometry · Mathematics 2023-10-19 Jasleen Kaur , Rajinder Kaur

The main purpose of this paper is to provide a structure theorem for codimension one singular transversely projective foliationson projective manifolds. To reach our goal, we firstly extend Corlette-Simpson's classification of rank two…

Algebraic Geometry · Mathematics 2016-07-05 Frank Loray , Frédéric Touzet , Jorge Vitorio Pereira

Given a semistable degeneration with a simple normal crossings central fiber, Abramovich-Chen-Gross-Siebert [3] proved a degeneration formula that relates the moduli spaces of stable maps in smooth fibers to certain moduli spaces of…

Symplectic Geometry · Mathematics 2020-07-20 Mohammad Farajzadeh Tehrani

We consider quasilinear elliptic systems in divergence form. In general, we cannot expect that weak solutions are locally bounded because of De Giorgi's counterexample. Here we assume a condition on the support of off-diagonal coefficients…

Analysis of PDEs · Mathematics 2019-11-15 Salvatore Leonardi , Francesco Leonetti , Cristina Pignotti , Eugenio Rocha , Vasile Staicu

We prove that a closed 3-orbifold that fibers over a hyperbolic polygonal 2-orbifold admits a family of hyperbolic cone structures that are viewed as regeneration of the polygon, provided that the perimeter is minimal.

Geometric Topology · Mathematics 2015-03-13 Joan Porti

A quasislit is the image of a vertical line segment [0, iy], y > 0, under a quasiconformal homeomorphism of the upper half-plane fixing infinity. Quasislits correspond precisely to curves generated by the Loewner equation with a driving…

Complex Variables · Mathematics 2019-10-09 Lukas Schoug , Atul Shekhar , Fredrik Viklund

The basic class of the non-integrable almost complex manifolds with a pair of Norden metrics are considered. The interconnections between corresponding quantities at the transformation between the two Levi-Civita connections are given. A…

Differential Geometry · Mathematics 2012-05-08 Dimitar Mekerov , Mancho Manev , Kostadin Gribachev

In this paper, we give a complete description of the deformation classes of real structures on minimal ruled surfaces. In particular, we show that these classes are determined by the topology of the real structure, which means that real…

Algebraic Geometry · Mathematics 2007-05-23 Jean-Yves Welschinger

Degenerations of linear series on smooth projective varieties approaching multicomponent varieties $X$ give rise to certain quiver representations in the category of linear series over $X$, which yield rational maps from $X$ to the…

Algebraic Geometry · Mathematics 2025-07-02 Eduardo Esteves , Piere Rodriguez , Eduardo Vital

It was recently proved that quasi-Fuchsian manifolds are uniquely determined by their bending laminations. This paper concerns a similar result for certain non-quasi-Fuchsian manifolds~: those obtained by degenerating one end but not the…

Geometric Topology · Mathematics 2025-11-17 Bruno Dular

This is, mostly, a survey of results about the birational geometry of rationally connected manifolds, using rational curves analogous to lines in ${\mathbb P}^n$ ({\it quasi-lines}). Various characterizations of a Zariski neighbourhood of a…

Algebraic Geometry · Mathematics 2007-05-23 Paltin Ionescu

Decompositions on manifolds appear in various geometric structures. Necessary and sufficient conditions for quotient spaces of decompositions to be manifolds are widely characterized. We characterize necessary and sufficient conditions to…

Geometric Topology · Mathematics 2022-02-16 Tomoo Yokoyama

In this paper, we study the moduli spaces of canonical threefolds with any prescribed geometric genus $p_g \ge 5$ which have the smallest possible canonical volume. This minimal volume is equal to the smallest half-integer that is larger…

Algebraic Geometry · Mathematics 2025-11-04 Stephen Coughlan , Yong Hu , Roberto Pignatelli , Tong Zhang

A cusp-decomposable manifold is a manifold constructed from a finite number of complete, negatively curved, finite volume manifolds and identifying the boundaries of truncated cusps by diffeomorphisms. Using properties of the electric space…

Geometric Topology · Mathematics 2020-10-09 Haydeé Contreras Peruyero

The paper sketches a recent progress and formulates several open problems in studying equivariant quasiconformal and quasisymmetric homeomorphisms in negatively curved spaces as well as geometry and topology of noncompact geometrically…

Differential Geometry · Mathematics 2009-09-07 Boris Apanasov