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Related papers: Local Euler obstructions of toric varieties

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In the previous paper (arXiv:0804.0701), the authors gave criteria for A_{k+1}-type singularities on wave fronts. Using them, we show in this paper that there is a duality between singular points and inflection points on wave fronts in the…

Differential Geometry · Mathematics 2010-05-12 Kentaro Saji , Masaaki Umehara , Kotaro Yamada

We explain how to form a novel dataset of simply connected Calabi-Yau threefolds via the Gross-Siebert algorithm. We expect these to degenerate to Calabi-Yau toric hypersurfaces with certain Gorenstein (not necessarily isolated)…

Algebraic Geometry · Mathematics 2021-09-22 Thomas Prince

Macpherson defined Chern-Schwartz-Macpherson (CSM) classes by introducing the (local) Euler obstruction function, which is an integer valued function on the variety that is constant on each stratum of a Whitney stratification of an…

Algebraic Geometry · Mathematics 2018-06-01 Jose Israel Rodriguez

We construct examples of projective toric surfaces whose blow-up at a general point has a non-polyhedral pseudo-effective cone, both in characteristic $0$ and in every prime characteristic $p$. As a consequence, we prove that the…

Algebraic Geometry · Mathematics 2021-10-26 Ana-Maria Castravet , Antonio Laface , Jenia Tevelev , Luca Ugaglia

Let $X$ be a non-singular compact K\"ahler manifold, endowed with an effective divisor $D= \sum (1-\beta_k) Y_k$ having simple normal crossing support, and satisfying $\beta_k \in (0,1)$. The natural objects one has to consider in order to…

Differential Geometry · Mathematics 2016-05-10 Henri Guenancia , Mihai Păun

Given a hypersurface in a complex projective space, we prove that the multidegrees of its toric polar map agree, up to sign, with the coefficients of the Chern-Schwartz-MacPherson class of a distinguished open set, namely the complement of…

Algebraic Geometry · Mathematics 2023-05-03 Thiago Fassarella , Nivaldo Medeiros , Rodrigo Salomão

We address the problem of necessary conditions and topological obstructions for the existence of robustly transitive maps on surfaces. Concretely, we show that partial hyperbolicity is a necessary condition in order to have $C^1$ robustly…

Dynamical Systems · Mathematics 2019-11-05 C. Lizana , W. Ranter

We show that equivariant elliptic genera of toric Calabi-Yau 3-folds are generalized weak Jacobi forms. We also introduce a notion of averaged equivariant elliptic genera of toric Calabi-Yau 3-folds, and show that they are ordinary weak…

Algebraic Geometry · Mathematics 2015-10-30 Jian Zhou

It is conjectured that the only integrable metrics on the two-dimensional torus are Liouville metrics. In this paper, we study a deformative version of this conjecture: We consider integrable deformations of a non-flat Liouville metric in a…

Dynamical Systems · Mathematics 2025-01-15 Joscha Henheik

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 survey recent developments in the study of torus equivariant motivic Chern and Hirzebruch characteristic classes of projective toric varieties, with applications to calculating equivariant Hirzebruch genera of torus-invariant Cartier…

Algebraic Geometry · Mathematics 2024-04-01 Sylvain E. Cappell , Laurenţiu Maxim , Jörg Schürmann , Julius L. Shaneson

We give a correspondence between toric 3-Sasaki 7-manifolds S and certain toric Sasaki-Einstein 5-manifolds M. These 5-manifolds are all diffeomorphic to k#(S^2\times S^3), where k=2b_2(S)+1, and are given by a pencil of Sasaki embeddings…

Differential Geometry · Mathematics 2012-08-09 Craig van Coevering

We construct and study the moduli of hypersurfaces in toric orbifolds. Let $X$ be a projective toric orbifold and $\alpha \in Cl(X)$ an ample class. The moduli space is constructed as a quotient of the linear system $|\alpha|$ by $G =…

Algebraic Geometry · Mathematics 2024-05-22 Dominic Bunnett

We consider blowups at a general point of weighted projective planes and, more generally, of toric surfaces with Picard number one. We give a unifying construction of negative curves on these blowups such that all previously known families…

Algebraic Geometry · Mathematics 2021-09-17 Javier González-Anaya , José Luis González , Kalle Karu

We prove a formula which compares intersection numbers of conormal varieties of two projective varieties and their dual varieties. When one of them is linear, we can recover the usual Plucker formula for the degree of the dual variety. The…

Algebraic Geometry · Mathematics 2007-05-23 Naichung Conan Leung

Using the algebraic geometric approach of Berenstein et {\it al} (hep-th/005087 and hep-th/009209) and methods of toric geometry, we study non commutative (NC) orbifolds of Calabi-Yau hypersurfaces in toric varieties with discrete torsion.…

High Energy Physics - Theory · Physics 2009-11-07 A. Belhaj , E. H. Saidi

A notion of duality of weight systems which corresponds to Batyrev's toric mirror symmetry is given. Explicit duality on the (1,1)-cohomology of K3 surfaces which are minimal models of toric hypersurfaces is constructed using monomial…

alg-geom · Mathematics 2008-02-03 Masanori Kobayashi

A 1930s conjecture of Hopf states that an even-dimensional compact Riemannian manifold with positive sectional curvature has positive Euler characteristic. We prove this conjecture under the additional assumption that the isometry group has…

Differential Geometry · Mathematics 2021-06-29 Lee Kennard , Michael Wiemeler , Burkhard Wilking

We prove a correspondence theorem for singular tropical surfaces in real three space, which recovers singular algebraic surfaces in an appropriate toric three-fold that tropicalize to a given singular tropical surface. Furthermore, we…

Algebraic Geometry · Mathematics 2018-08-24 Hannah Markwig , Thomas Markwig , Eugenii Shustin

Weighted quadratic estimates are proved for certain bisectorial firstorder differential operators with bounded measurable coefficients which are (not necessarily pointwise) accretive, on complete manifolds with positive injectivity radius.…

Analysis of PDEs · Mathematics 2024-05-29 Pascal Auscher , Andrew J. Morris , Andreas Rosén