English
Related papers

Related papers: Amoebas of half-dimensional varieties

200 papers

The problem of determining the volume of a tubular neighbourhood has a long and rich history. Bounds on the volume of neighbourhoods of algebraic sets have turned out to play an important role in the probabilistic analysis of condition…

Numerical Analysis · Mathematics 2013-10-01 Martin Lotz

We provide a clarification of the classification of two-dimensional algebras over an arbitrary base field. Using this clarification, we determine the number of non-isomorphic two-dimensional algebras over a finite field.

Rings and Algebras · Mathematics 2026-05-26 U. Bekbaev

We call a partially hyperbolic diffeomorphism \emph{partially volume expanding} if the Jacobian restricted to any hyperplane that contains the unstable bundle $E^u$ is larger than $1$. This is a $C^1$ open property. We show that any…

Dynamical Systems · Mathematics 2021-02-24 Shaobo Gan , Ming Li , Marcelo Viana , Jiagang Yang

We give a lower bound for the degree of a finite cover of a hyperbolic 3-manifold which fibers over the circle, in terms of volume, the diameter of the manifold and other new invariants.

Geometric Topology · Mathematics 2021-09-23 Inkang Kim , Hongbin Sun

The computation of amoebas has been a challenging open problem for the last dozen years. The most natural approach, namely to compute an amoeba via its boundary, has not been practical so far since only a superset of the boundary, the…

Algebraic Geometry · Mathematics 2016-06-14 Franziska Schroeter , Timo de Wolff

We prove matching asymptotic lower and upper bounds on the variances of the intrinsic volumes and the number of $k$-faces of $d$-dimensional random beta-polytopes. Using Stein's methods, we establish central limit theorems for the intrinsic…

Metric Geometry · Mathematics 2025-12-04 Ferenc Fodor , Balázs Grünfelder

It is shown that tube sets over amoebas of algebraic varieties (and, more generally, of almost periodic holomorphic chains) of dimension q are q-pseudoconcave in the sense of Rothstein. This is a direct consequence of a representation of…

Complex Variables · Mathematics 2010-01-14 Alexander Rashkovskii

Our main result is that every n-dimensional polytope can be described by at most (2n-1) polynomial inequalities and, moreover, these polynomials can explicitly be constructed. For an n-dimensional pointed polyhedral cone we prove the bound…

Metric Geometry · Mathematics 2007-05-23 Hartwig Bosse , Martin Groetschel , Martin Henk

We provide new, improved lower bounds for the Hodge and Frobenius colevels of algebraic varieties (over $\mathbf{C}$ or over a finite field) in all cohomological degrees. These bounds are expressed in terms of the dimension of the variety…

Algebraic Geometry · Mathematics 2025-04-23 Daqing Wan , Dingxin Zhang

Let N be a compact, orientable hyperbolic 3-manifold with connected, totally geodesic boundary of genus 2. If N has Heegaard genus at least 5, then its volume is greater than 6.89. The proof of this result uses the following dichotomy:…

Geometric Topology · Mathematics 2009-02-04 Jason DeBlois , Peter B. Shalen

We study smooth projective complex varieties with ample cotangent bundle. Our main result is that in an abelian variety of dimension n, a complete intersection of at least n/2 general hypersurfaces of sufficiently high degrees has ample…

Algebraic Geometry · Mathematics 2011-09-08 O. Debarre

The amoeba of a Laurent polynomial $f \in \C[z_1^{\pm 1},\ldots,z_n^{\pm 1}]$ is the image of its zero set $\mathcal{V}(f)$ under the log-absolute-value map. Understanding the space of amoebas (i.e., the decomposition of the space of all…

Algebraic Geometry · Mathematics 2013-04-24 Thorsten Theobald , Timo de Wolff

It is known that the volume function for hyperbolic manifolds of dimension $\geq 3$ is finite-to-one. We show that the number of nonhomeomorphic hyperbolic 4-manifolds with the same volume can be made arbitrarily large. This is done by…

Geometric Topology · Mathematics 2016-09-07 Dubravko Ivanšić

A coamoeba is the image of a subvariety of a complex torus under the argument map to the real torus. Similarly, a non-archimedean coamoeba is the image of a subvariety of a torus over a non-archimedean field with complex residue field under…

Algebraic Geometry · Mathematics 2011-10-06 Mounir Nisse , Frank Sottile

In this paper, we define a new conformal invariant on complete non-compact hyperbolic surfaces that can be conformally compactified to bounded domains in $\mathbb{C}$. We study and compute this invariant up to one-connected surfaces. Our…

Differential Geometry · Mathematics 2025-01-01 Jinyang Wu

We give an alternative representation of the closure of the Bochner transform of a holomorphic almost periodic mapping in a tube domain. For such mappings we introduce a new notion of amoeba and we show that, for mappings which are regular…

Complex Variables · Mathematics 2011-09-15 Adelina Fabiano , Jacques Guenot , James Silipo

A uniform bound of intersection multiplicities of curves and divisors on abelian varieties is proved by algebraic geometric methods. It extends and improves a result obtained by A. Buium with a different method based on Kolchin's…

Algebraic Geometry · Mathematics 2007-05-23 Junjiro Noguchi , Joerg Winkelmann

For closed and oriented hyperbolic surfaces, a formula of Witten establishes an equality between two volume forms on the space of representations of the surface in a semisimple Lie group. One of the forms is a Reidemeister torsion, the…

Geometric Topology · Mathematics 2020-10-28 Michael Heusener , Joan Porti

We prove that a quasi-finite endomorphism of an algebraic variety over an algebraically closed field of characteristic zero, that is injective on the complement of a closed subvariety, is an automorphism. We also prove that an endomorphism…

Algebraic Geometry · Mathematics 2021-04-02 Nilkantha Das

In this paper we study volumes of moduli spaces of hyperbolic surfaces with geodesic, cusp and cone boundary components. We compute the volumes in some new cases, in particular when there exists a large cone angle. This allows us to give…

Algebraic Geometry · Mathematics 2025-06-18 Lukas Anagnostou , Paul Norbury