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Related papers: Deformation types of real and complex manifolds

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We investigate deformations of lagrangian manifolds with singularities. We introduce a complex similar to the de Rham-complex whose cohomology calculates deformation spaces. Examples of singular lagrangian varieties are presented and…

Algebraic Geometry · Mathematics 2007-05-23 Duco van Straten , Christian Sevenheck

In two former papers, the authors independently proved that the space of hyperbolic cone-3-manifolds with cone angles less than 2{\pi} and fixed singular locus is locally parametrized by the cone angles. In this sequel, we investigate the…

Differential Geometry · Mathematics 2014-11-11 Grégoire Montcouquiol , Hartmut Weiß

Topology and geometry are deeply intertwined in the study of surfaces, though their interaction manifests differently in smooth and discrete settings. In the smooth category, a classical result asserts that any closed smooth surface…

Differential Geometry · Mathematics 2025-12-23 Soto Hisakawa , Shizuo Kaji , Ryo Kawai

According to our previous results, the conjugacy class of the involution induced by the complex conjugation in the homology of a real non-singular cubic fourfold determines the fourfold up to projective equivalence and deformation. Here, we…

Algebraic Geometry · Mathematics 2019-02-20 S. Finashin , V. Kharlamov

We approach the question of complexification of the diffeomorphism group of the circle by considering real-analytic maps from the circle into the punctured complex plane with winding number +1. Such complex deformations form an…

Mathematical Physics · Physics 2026-05-20 Sid Maibach , Eveliina Peltola

We study the global invariants of real analytic manifolds in the complex space with respect to the group of holomorphic unimodular transformations. We consider only totally real manifolds which admits a certain fibration over the circle. We…

Complex Variables · Mathematics 2009-09-25 Xianghong Gong

We study Willmore surfaces of constant Moebius curvature $K$ in $S^4$. It is proved that such a surface in $S^3$ must be part of a minimal surface in $R^3$ or the Clifford torus. Another result in this paper is that an isotropic surface…

Differential Geometry · Mathematics 2007-09-12 Xiang Ma , Changping Wang

In this article we study the deformations of hyperelliptic polarized varieties $(X,L)$ of dimension $m$ and sectional genus $g$ such that the image $Y$ of the morphism $\varphi$ induced by $|L|$ is smooth. If $L^m < 2g-2$, it is known that,…

Algebraic Geometry · Mathematics 2020-05-04 Purnaprajna Bangere , Francisco Javier Gallego , Miguel González

We prove a Kuranishi-type theorem for deformations of complex structures on ALE K\"ahler surfaces. This is used to prove that for any scalar-flat K\"ahler ALE surface, all small deformations of complex structure also admit scalar-flat…

Differential Geometry · Mathematics 2018-09-18 Jiyuan Han , Jeff A. Viaclovsky

For a compact complex manifold, we introduce holomorphic foliations associated with certain abelian subgroups of the automorphism group. Such foliations are generalizations of holomorphic principal torus bundles. If there exists a…

Complex Variables · Mathematics 2018-01-22 Hiroaki Ishida , Hisashi Kasuya

Given a semisimple Frobenius manifold, we construct a class of integrable deformations of its hierarchy of topological type. We show that these integrable deformations have polynomial tau-structures, and conjecture that for the…

Mathematical Physics · Physics 2025-11-11 Si-Qi Liu , Paolo Rossi , Di Yang , Youjin Zhang

We study real elliptic surfaces and trigonal curves (over a base of an arbitrary genus) and their equivariant deformations. We calculate the real Tate-Shafarevich group and reduce the deformation classification to the combinatorics of a…

Algebraic Geometry · Mathematics 2009-02-13 Alex Degtyarev , Ilia Itenberg , Viatcheslav Kharlamov

Given a compact Fano K\"ahler manifold (M,J) with a K\"ahler Ricci soliton g, we consider smooth families {J_t} of complex deformations of (M,J) which are invariant under the action of a maximal torus T in the full isometry group of (M,g).…

Differential Geometry · Mathematics 2012-06-11 Fabio Podesta' , Andrea Spiro

The main purpose of this article is to develop an explicit derived deformation theory of algebraic structures at a high level of generality, encompassing in a common framework various kinds of algebras (associative, commutative, Poisson...)…

Algebraic Topology · Mathematics 2025-03-11 Gregory Ginot , Sinan Yalin

In this article, we study the moduli of irregular surfaces of general type with at worst canonical singularities satisfying $K_X^2 = 4p_g(X)-8$, for any even integer $p_g\geq 4$. These surfaces also have unbounded irregularity $q$. We carry…

Algebraic Geometry · Mathematics 2022-12-19 Purnaprajna Bangere , Francisco Javier Gallego , Jayan Mukherjee , Debaditya Raychaudhury

For each closed orientable surface we introduce a simplical complex with some additional structure which is a version of the complex of curves of this surface adjusted to investigation of its Torelli group. We call this complex the Torelli…

Geometric Topology · Mathematics 2007-05-23 Benson Farb , Nikolai V. Ivanov

In 1949 Siegel gave an example of a complex two-torus with no nonconstant meromorphic functions. In 1964 Kodaira showed that compact complex surfaces with no nonconstant meromorphic must be of the following three types: tori, Hopf type…

Complex Variables · Mathematics 2018-05-23 Raymond O. Wells

In this paper we investigate fixed-point numbers of endomorphisms on complex tori. Specifically, motivated by the asymptotic perspective that has turned out in recent years to be so fruitful in Algebraic Geometry, we study how the number of…

Algebraic Geometry · Mathematics 2015-08-26 Thomas Bauer , Thorsten Herrig

Consider the functor describing deformations of a representation of the fundamental group of a variety X. This paper is chiefly concerned with establishing an analogue in finite characteristic of a result proved by Goldman and Millson for…

Algebraic Geometry · Mathematics 2019-07-04 J. P. Pridham

We consider unitary cocycle deformations of covariant $\ast$-differential calculi. We prove that complex structures, holomorphic bimodules and Chern connections on the deformed calculus are twists of their untwisted counterparts. Moreover,…

Quantum Algebra · Mathematics 2026-02-19 Jyotishman Bhowmick , Bappa Ghosh