English
Related papers

Related papers: Exponential rarefaction of real curves with many c…

200 papers

We survey the distributional properties of progressively dilating sets under projection by covering maps, focusing on manifolds of constant sectional curvature. In the Euclidean case, we review previously known results and formulate some…

Dynamical Systems · Mathematics 2024-09-10 Emilio Corso

We show that a generic real projective n-dimensional hypersurface of degree 2n-1 contains "many" real lines, namely, not less than (2n-1)!!, which is approximately the square root of the number of complex lines. This estimate is based on…

Algebraic Geometry · Mathematics 2012-06-26 S. Finashin , V. Kharlamov

In this note, we obtain various formulas for the curvature of the $L^2$ metric on the direct image of the relative canonical bundle twisted by a holomorphic line bundle endowed with a positively curved metric with analytic singularities,…

Complex Variables · Mathematics 2021-02-05 Junyan Cao , Henri Guenancia , Mihai Păun

We partly extend the localisation technique from convex geometry to the multiple constraints setting. For a given $1$-Lipschitz map $u\colon\mathbb{R}^n\to\mathbb{R}^m$, $m\leq n$, we define and prove the existence of a partition of…

Metric Geometry · Mathematics 2021-08-17 Krzysztof J. Ciosmak

Let $X$ be a finite simply connected CW complex of dimension $n$. The loop space homology $H\_*(\Omega X;\mathbb Q)$ is the universal enveloping algebra of a graded Lie algebra $L\_X$ isomorphic with $ pi\_{*-1} (X)\otimes \mathbb Q$. Let…

Algebraic Topology · Mathematics 2016-08-16 Yves Félix , Steve Halperin , Jean-Claude Thomas

We transform the positive-genus real Gromov-Witten invariants of many real-orientable symplectic threefolds into signed counts of curves. These integer invariants provide lower bounds for counts of real curves of a given genus that pass…

Algebraic Geometry · Mathematics 2015-11-09 Jingchen Niu , Aleksey Zinger

We compute some numerical invariants of the lines on hyperplane sections of a smooth cubic threefold over complex numbers. We also prove that for any smooth hypersurface $X\subset \mathbb P^{n+1}$ of degree $d$ over an algebraically closed…

Algebraic Geometry · Mathematics 2020-07-08 Yiran Cheng

Let $X$ be a smooth projective toric variety over $Spec(Z)$. Let $\bar{\mathcal{O}(D)}$ be an equivariant hermitian line bundle on $X$, equipped with a positive metric and invariant under the action of the compact torus of $X(C)$, we…

Algebraic Geometry · Mathematics 2014-03-14 Mounir Hajli

We initiate the study of a class of real plane algebraic curves which we call expressive. These are the curves whose defining polynomial has the smallest number of critical points allowed by the topology of the set of real points of a…

Algebraic Geometry · Mathematics 2023-08-29 Sergey Fomin , Eugenii Shustin

We consider the germ of a reduced curve, possibly reducible. F.Delgado de la Mata proved that such a curve is Gorenstein if and only if its semigroup of values is symmetrical. We extend here this symmetry property to any fractional ideal of…

Algebraic Geometry · Mathematics 2017-09-06 Delphine Pol

When identified with sequences of irreducible Hermitian-Einstein connections, sequences of stable holomorphic bundles of fixed topological type and bounded degree on a compact complex surface equipped with a Gauduchon metric are shown to…

alg-geom · Mathematics 2008-02-03 Nicholas P. Buchdahl

Let $M^{n+1}$ be a closed manifold of dimension $3\le n+1\le 7$ equipped with a generic Riemannian metric $g$. Let $c$ be a positive number. We show that, either there exist infinitely many distinct closed hypersurfaces with constant mean…

Differential Geometry · Mathematics 2024-08-27 Liam Mazurowski , Xin Zhou

We compute the stable reduction of some Galois covers of the projective line branched at three points. These covers are constructed using Hurwitz spaces parameterizing metacyclic covers. The reduction is determined by a hypergeometric…

Algebraic Geometry · Mathematics 2007-05-23 Irene I. Bouw

We obtain a complete list of smooth projective threefolds over $\mathbb C$ for which the dimension of the space of vanishing cycles (in $H^2$ of the smooth hyperplane section) equals $2$. We also obtain a complete list of rank 2 very ample…

Algebraic Geometry · Mathematics 2025-06-03 Timofey Fedorov

This article is concerned with the convexity properties of universal covers of projective varieties. We study the relation between the convexity properties of the universal cover of X and the properties of the pullback map sending vector…

Algebraic Geometry · Mathematics 2007-05-23 F. Bogomolov , B. De Oliveira

We prove a simple equivalence between the virtual count of rational curves in the total space of an anti-nef line bundle and the virtual count of rational curves maximally tangent to a smooth section of the dual line bundle. We conjecture a…

Algebraic Geometry · Mathematics 2020-01-09 Michel van Garrel , Tom Graber , Helge Ruddat

We prove the macroscopic cousins of three conjectures: 1) a conjectural bound of the simplicial volume of a Riemannian manifold in the presence of a lower scalar curvature bound, 2) the conjecture that rationally essential manifolds do not…

Differential Geometry · Mathematics 2021-11-09 Sabine Braun , Roman Sauer

The $X$-rank of a point $p$ in projective space is the minimal number of points of an algebraic variety $X$ whose linear span contains $p$. This notion is naturally submultiplicative under tensor product. We study geometric conditions that…

Algebraic Geometry · Mathematics 2020-05-29 Edoardo Ballico , Alessandra Bernardi , Fulvio Gesmundo , Alessandro Oneto , Emanuele Ventura

For a certain parametrized family of maps on the circle, with critical points and logarithmic singularities where derivatives blow up to infinity, a positive measure set of parameters was constructed in [19], corresponding to maps which…

Dynamical Systems · Mathematics 2012-02-07 Hiroki Takahasi

We define the notion of special Lagrangian curvature, showing how it may be interpreted as an alternative higher dimensional generalisation of two dimensional Gaussian curvature. We obtain first a local rigidity result for this curvature…

Differential Geometry · Mathematics 2008-07-16 Graham Smith