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Related papers: Intersections of Amoebas

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An amoeba is the image of a subvariety of an algebraic torus under the logarithmic moment map. We consider some qualitative aspects of amoebas, establishing some results and posing problems for further study. These problems include…

Algebraic Geometry · Mathematics 2022-06-22 Mounir Nisse , Frank Sottile

In this note, we investigate the maximal number of intersection points of a line with the contour of hypersurface amoebas in $\mathbb{R}^n$. We define the latter number to be the $\mathbb{R}$-degree of the contour. We also investigate the…

Algebraic Geometry · Mathematics 2019-05-21 Lionel Lang , Boris Shapiro , Eugenii Shustin

To any algebraic curve A in a complex 2-torus $(\C^*)^2$ one may associate a closed infinite region in a real plane called the amoeba of A. The amoebas of different curves of the same degree come in different shapes and sizes. All amoebas…

Complex Variables · Mathematics 2007-05-23 Grigory Mikhalkin , Hans Rullgard

We show that the amoeba of a generic complex algebraic variety of codimension $1<r<n$ do not have a finite basis. In other words, it is not the intersection of finitely many hypersurface amoebas. Moreover we give a geometric…

Algebraic Geometry · Mathematics 2014-03-18 Mounir Nisse

We prove a symmetric version of B\'ezout's theorem. More precisely, we show that the symmetric orbit type of a transverse intersection of complex symmetric hypersurfaces in projective space is determined by the degrees. In the projective…

Algebraic Geometry · Mathematics 2024-10-01 Samuel Lidz , Zachary Lihn , Adam Melrod

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 investigate the real algebraic complexity of contours of amoebas associated with algebraic hypersurfaces and complete intersections in complex algebraic tori. Motivated by the foundational estimates of Lang--Shapiro--Shustin \cite{LSS},…

Algebraic Geometry · Mathematics 2026-05-26 Mounir Nisse

This survey consists of two parts. Part 1 is devoted to amoebas. These are images of algebraic subvarieties in the complex torus under the logarithmic moment map. The amoebas have essentially piecewise-linear shape if viewed at large.…

Algebraic Geometry · Mathematics 2007-05-23 Grigory Mikhalkin

An $n$-dimensional algebraic variety in $({\mathbb C}^\times)^{2n}$ covers its amoeba as well as its coamoeba generically finite-to-one. We provide an upper bound for the volume of these amoebas as well as for the number of points in the…

Algebraic Geometry · Mathematics 2015-09-01 Grigory Mikhalkin

We show that the amoeba of a complex algebraic variety defined as the solutions to a generic system of $n$ polynomials in $n$ variables has a finite basis. In other words, it is the intersection of finitely many hypersurface amoebas.…

Algebraic Geometry · Mathematics 2014-04-15 Mounir Nisse

The study of hypersurfaces in a torus leads to the beautiful zoo of amoebas and their contours, whose possible configurations are seen from combinatorial data. There is a deep connection to the logarithmic Gauss map and its critical points.…

Complex Variables · Mathematics 2012-02-22 Bernd Martin , Dmitry Pochekutov

The classical version of B\'ezout's Theorem gives an integer-valued count of the intersection points of hypersurfaces in projective space over an algebraically closed field. Using work of Kass and Wickelgren, we prove a version of…

Algebraic Geometry · Mathematics 2021-04-20 Stephen McKean

The coamoeba of any complex algebraic plane curve $V$ is its image in the real torus under the argument map. The area counted with multiplicity of the coamoeba of any algebraic curve in $(\mathbb{C}^*)^2$ is bounded in terms of the degree…

Algebraic Geometry · Mathematics 2008-10-27 Mounir Nisse

Classically, B\'ezout's theorem says that an intersection of hypersurfaces in a projective space is rationally equivalent to a number of copies of a smaller projective space, the number depending on the degrees of the hypersurfaces. We give…

Algebraic Topology · Mathematics 2023-12-04 Steven R. Costenoble , Thomas Hudson

This paper offers a systematic study of a family of graphs called amoebas. Amoebas recently emerged from the study of forced patterns in $2$-colorings of the edges of the complete graph in the context of Ramsey-Turan theory and played an…

Combinatorics · Mathematics 2023-06-02 Yair Caro , Adriana Hansberg , Amanda Montejano

Global amoebas are a wide and rich family of graphs that emerged from the study of certain Ramsey-Tur\'an problems in $2$-colorings of the edges of the complete graph $K_n$ that deal with the appearance of unavoidable patterns once a…

Combinatorics · Mathematics 2021-04-21 Adriana Hansberg , Amanda Montejano , Yair Caro

This paper is a report based on the results obtained during a three months internship at the University of Pittsburgh by the first author and under the mentorship of the second author. The notion of an amoeba of a subvariety in a torus…

Algebraic Geometry · Mathematics 2022-12-07 Rémi Delloque , Kiumars Kaveh

The amoebas associated to algebraic varieties are certain concave regions in the Euclidean space whose shape reminds biological amoebas. This term was formally introduced to Mathematics in 1994 by Gelfand, Kapranov and Zelevinski. Some…

Algebraic Geometry · Mathematics 2007-05-23 Grigory Mikhalkin

The paper deals with singularities of nonconfluent hypergeometric functions in several variables. Typically such a function is a multi-valued analytic function with singularities along an algebraic hypersurface. We describe such…

Complex Variables · Mathematics 2007-05-23 Mikael Passare , Timur Sadykov , August Tsikh

Let $V$ be a complex algebraic hypersurface defined by a polynomial $f$ with Newton polytope $\Delta$. It is well known that the spine of its amoeba has a structure of a tropical hypersurface. We prove in this paper that there exists a…

Algebraic Geometry · Mathematics 2009-12-05 Mounir Nisse
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