English
Related papers

Related papers: Unstable Kodaira Fibrations

200 papers

In this article we study asymptotic slopes of strongly semistable vector bundles on a smooth projective surface. A connection between asymptotic slopes and strong restriction theorem of a strongly semistable vector bundle is shown. We also…

Algebraic Geometry · Mathematics 2022-01-10 Mitra Koley , A. J. Parameswaran

Polyhedral K\"ahler surfaces are a class of complex surfaces, which are flat everywhere except on a two-dimensional skeleton. They are defined as a generalisation of the "gluing a polygon side by side" construction of flat Riemann surfaces.…

Algebraic Geometry · Mathematics 2018-06-11 Cécile Gachet

Let $X$ be the Jacobian of a genus 2 curve $\widetilde{\mathcal{C}}$ over $\mathbb{C}$ and $Y$ be the associated Kummer surface. Consider an ample line bundle $L=O(m\widetilde{\mathcal{C}})$ on $X$ for an even number $m$, and its descent to…

Algebraic Geometry · Mathematics 2017-03-21 Poornapushkala Narayanan

A classical result of Miyanishi-Sugie and Keel-McKernan asserts that for smooth affine surfaces, affine-uniruledness is equivalent to affine-ruledness, both properties being in fact equivalent to the negativity of the logarithmic Kodaira…

Algebraic Geometry · Mathematics 2012-12-04 Adrien Dubouloz , Takashi Kishimoto

For each $k\geq2$, we construct two families of surfaces with constant mean curvature $H$ for $H\in[0,1/2]$ in $\Sigma(\kappa)\times\R$ where $\kappa+4H^2\leq0$. The surfaces are invariant under $2\pi/k$-rotations about a vertical fiber of…

Differential Geometry · Mathematics 2013-06-04 Julia Plehnert

Given an etale quotient q:X->Y of smooth projective varieties we relate the simple Seshadri constant of a line bundle M on Y with the multiple Seshadri constant of q*M in the points of the fiber. We apply this method to compute the Seshadri…

Algebraic Geometry · Mathematics 2007-05-23 Luis Fuentes Garcia

Let F be a finite field and let C be a smooth projective curve over F. For some smooth projective surfaces X over F we establish that the third unramified cohomology of the product of X and C vanishes. This applies in particular to…

Algebraic Geometry · Mathematics 2012-03-12 Alena Pirutka

We give a criterion for the sheaf of K\"ahler differentials on a cone over a smooth projective variety to be torsion-free. Applying this to Veronese embeddings of projective space and using known results on differentials on quotient…

Algebraic Geometry · Mathematics 2015-04-17 Daniel Greb , Sönke Rollenske

We describe a family of smooth contractible algebraic surfaces $X$ different from $\C^2$ such that $X$ admits dominant holomorphic maps from $\C^2$ and there is a unique line $E$ in $X$ for which the Kobayashi-Royden pseudometric vanishes…

Complex Variables · Mathematics 2025-09-09 Shulim Kaliman

The effects of thermal noise on particle rearrangements in colloidal suspensions undergoing cyclic shear are experimentally investigated using particle tracking methods. The experimental model system consists of polystyrene particles…

Soft Condensed Matter · Physics 2017-10-16 Somayeh Farhadi , Paulo E. Arratia

We prove K-stability for infinitely many smooth members of the family 2.19 of the Mukai-Mori classification.

Algebraic Geometry · Mathematics 2024-12-25 Tiago Duarte Guerreiro , Luca Giovenzana , Nivedita Viswanathan

We study the stability of compact pseudo-K\"ahler manifolds, i.e. compact complex manifolds $X$ endowed with a symplectic form compatible with the complex structure of $X$. When the corresponding metric is positive-definite, $X$ is K\"ahler…

Differential Geometry · Mathematics 2020-01-15 Adela Latorre , Luis Ugarte

We give an existence result on (H,A)-stable sheaves on a K3 or abelian surface X with primitive triple of invariants (rank,first Chern class,Euler characteristics) in the integral cohomology lattice. Such a result yields the existence of…

Algebraic Geometry · Mathematics 2013-02-21 Markus Zowislok

We study holomorphic foliations of aribitrary codimension in smooth complete toric varieties. We show that split foliations are stable if some good behaviour of their singular set is provided. As an application of these results, we exhibit…

Algebraic Geometry · Mathematics 2022-01-25 Sebastián Velazquez

This is a survey of recent examples of varieties that are not stably rational. We review the specialization method based on properties of the Chow group of zero-cycles used in these examples and explain the point of view of unramified…

Algebraic Geometry · Mathematics 2016-08-29 Alena Pirutka

We define K-stability of a polarized Sasakian manifold relative to a maximal torus of automorphisms. The existence of a Sasaki-extremal metric in the polarization is shown to imply that the polarization is K-semistable. Computing this…

Differential Geometry · Mathematics 2018-08-10 Charles P. Boyer , Craig van Coevering

In this follow up work to [45, 33, 32, 46] we introduce and study a notion of geodesic stability restricted to rays with prescribed singularity types. A number of notions of interest fit into this framework, in particular algebraic- and…

Differential Geometry · Mathematics 2018-12-31 Zakarias Sjöström Dyrefelt

It is in general unknown which topological complex vector bundles on a non-algebraic surface admit holomorphic structures. We solve this problem for primary Kodaira surfaces by using results of Kani on curves of genus two with elliptic…

Complex Variables · Mathematics 2013-11-21 Marian Aprodu , Vasile Brinzanescu , Matei Toma

Consider a family f:A --> U of g-dimensional abelian varieties over a quasiprojective manifold U. Suppose that the induced map from U to the moduli scheme of polarized abelian varieties is generically finite and that there is a projective…

Algebraic Geometry · Mathematics 2009-10-12 Martin Moeller , Eckart Viehweg , Kang Zuo

Fujita's second theorem for K\"ahler fibre spaces over a curve asserts that the direct image $V$ of the relative dualizing sheaf splits as the direct sum $ V = A \oplus Q$, where $A$ is ample and $Q$ is unitary flat. We focus on our…

Algebraic Geometry · Mathematics 2016-05-11 Fabrizio Catanese , Michael Dettweiler