English
Related papers

Related papers: Stratification of Projection Maps From Toric Varie…

200 papers

We discuss an experimental approach to open problems in toric geometry: are smooth projective toric varieties (i) projectively normal and (ii) defined by degree 2 equations? We discuss the creation of lattice polytopes defining smooth toric…

Algebraic Geometry · Mathematics 2013-01-29 Winfried Bruns

We describe a new algorithm for computing Whitney stratifications of complex projective varieties. The main ingredients are (a) an algebraic criterion, due to L\^e and Teissier, which reformulates Whitney regularity in terms of conormal…

Algebraic Geometry · Mathematics 2022-12-29 Martin Helmer , Vidit Nanda

We use localization to describe the restriction map from equivariant Chow cohomology to ordinary Chow cohomology for complete toric varieties in terms of piecewise polynomial functions and Minkowski weights. We compute examples showing that…

Algebraic Geometry · Mathematics 2008-12-07 Eric Katz , Sam Payne

We show that strata of oriented toric hyperplane arrangements are in bijection with a collection of lattice points in a zonotope. Moreover, we relate the dimension of the stratum and the dimension of the minimal face of the zonotope…

Combinatorics · Mathematics 2025-10-16 Friedrich Bauermeister , Andrew Hanlon , Davis Painter , Sair Shaikh , Benjamin Singer

Given a toric degeneration (a degeneration to a toric variety), over the complex numbers, we construct a surjective continuous map from a general fiber to the special fiber of the degeneration in the classical topology. The construction is…

Algebraic Geometry · Mathematics 2025-11-04 Takuya Murata , Lara Bossinger

This article shows that every non-isotropic harmonic 2-torus in complex projective space factors through a generalised Jacobi variety related to the spectral curve. Each map is composed of a homomorphism into the variety and a rational map…

Differential Geometry · Mathematics 2007-05-23 Ian McIntosh

In a previous paper, we provided some update in the treatment of the finiteness theorem for rational maps of finite degree from a fixed variety to varieties of general type. In the present paper we present another improvement, introducing…

Algebraic Geometry · Mathematics 2012-03-13 Lucio Guerra , Gian Pietro Pirola

We describe new algorithms to compute Whitney stratifications of real algebraic varieties. Using either conormal or polar techniques, these algorithms stratify a complexification of a given real variety. We then show that the resulting…

Algebraic Geometry · Mathematics 2025-09-03 Martin Helmer , Anton Leykin , Vidit Nanda

By analogy with algebraic geometry, we define a category of non-linear sheaves (quasi-coherent homotopy-sheaves of topological spaces) on projective toric varieties and prove a splitting result for its algebraic K-theory, generalising…

K-Theory and Homology · Mathematics 2010-07-30 Thomas Huettemann

Toric geometry provides a bridge between the theory of polytopes and algebraic geometry: one can associate to each lattice polytope a polarized toric variety. In this thesis we explore this correspondence to classify smooth lattice…

Algebraic Geometry · Mathematics 2013-07-05 Douglas Monsôres

A stratification of a singular set, e.g. an algebraic or analytic variety, is, roughly, a partition of it into manifolds so that these manifolds fit together "regularly". A classical theorem of Whitney says that any complex analytic set has…

Algebraic Geometry · Mathematics 2007-05-23 Vadim Kaloshin

Using Morita type stratifications, we establish a one-to-one correspondence between geometric vector fields on a separated differentiable stack and stratified vector fields on its orbit space. This correspondence enables us to derive a…

Differential Geometry · Mathematics 2026-05-06 Mateus de Melo , Juan Sebastian Herrera-Carmona , Fabricio Valencia

We study the GKM theory for a equivariant stratified space having orbifold structures in tis successive quotients. Then, we introduce the notion of an \emph{almost simple polytope}, as well as a \emph{divisive toric variety} generalizing…

Algebraic Topology · Mathematics 2020-12-03 Soumen Sarkar , Jongbaek Song

Let $X\subset\Bbb C^n$ be an affine variety and $f:X\to\Bbb C^m$ be the restriction to $X$ of a polynomial map $\Bbb C^n\to\Bbb C^m$. In this paper, we construct an affine Whitney stratification of $X$. The set $K(f)$ of stratified…

Algebraic Geometry · Mathematics 2018-07-06 Si Tiep Dinh , Zbigniew Jelonek

This note proves the existence of universal rational parametrizations. The description involves homogeneous coordinates on a toric variety coming from a lattice polytope. We first describe how smooth toric varieties lead to universal…

Algebraic Geometry · Mathematics 2007-05-23 David Cox , Rimvydas Krasauskas , Mircea Mustata

The Cox ring provides a coordinate system on a toric variety analogous to the homogeneous coordinate ring of projective space. Rational maps between projective spaces are described using polynomials in the coordinate ring, and we generalise…

Algebraic Geometry · Mathematics 2014-06-02 Gavin Brown , Jarosław Buczyński

We establish Thom's jet transversality theorem for regular maps from an affine algebraic manifold to an algebraic manifold satisfying a suitable flexibility condition. It can be considered as the algebraic version of Forstneri\v{c}'s jet…

Algebraic Geometry · Mathematics 2022-12-13 Yuta Kusakabe

In this survey I summarize the constructions of toric degenerations obtained from valuations and Gr\"obner theory and describe in which sense they are equivalent. I show how adapted bases can be used to generalize the classical Newton…

Algebraic Geometry · Mathematics 2023-01-09 Lara Bossinger

We describe the topology of a general polynomial mapping $f:\Bbb C^2\to\Bbb C^2.$

Algebraic Geometry · Mathematics 2016-02-09 M. Farnik , Z. Jelonek , M. A. S. Ruas

An extension of the Tamari lattice to the multiplihedra is discussed, along with projections to the composihedra and the Boolean lattice. The multiplihedra and composihedra are sequences of polytopes that arose in algebraic topology and…

Combinatorics · Mathematics 2015-03-19 Stefan Forcey
‹ Prev 1 2 3 10 Next ›