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Related papers: Embedded desingularization of toric varieties

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Let $X$ be an $n$-dimensional smooth complex projective variety embedded in $\mathbb{C}\mathbb{P}^{N}$. We construct a smooth family $\mathcal{X}$ over $\mathbb{C}$ with an embedding in $\mathbb{C}\mathbb{P}^{N} \times \mathbb{C}$ whose…

Symplectic Geometry · Mathematics 2018-09-26 Kiumars Kaveh

We show that any normal toric variety over a rank one valuation ring admits an equivariant open embedding in a normal toric variety which is proper over the valuation ring, after a base-change by a finite extension of valuation rings. If…

Algebraic Geometry · Mathematics 2019-08-02 Netanel Friedenberg

Associated to a toric variety $X$ of dimension $r$ over a field $k$ is a fan $\Delta$ on $\Bbb R^r$. The fan $\Delta$ is a finite set of cones which are in one-to-one correspondence with the orbits of the torus action on $X$. The fan…

alg-geom · Mathematics 2008-02-03 Timothy J. Ford

In this paper we construct a degeneration of Bott-Samelson-Demazure-Hansen varieties to toric varieties in an algebraic family and study the geometry of the resulting toric varieties. We give a natural set of torus invariant curves that…

Algebraic Geometry · Mathematics 2016-04-08 A. J Parameswaran , Paramasamy Karuppuchamy

Let $\Sigma$ and $\Sigma'$ be two refinements of a fan $\Sigma_0$ and $f \colon X_{\Sigma} \dashrightarrow X_{\Sigma'}$ be the birational map induced by $X_{\Sigma} \rightarrow X_{\Sigma_0} \leftarrow X_{\Sigma'}$. We show that the graph…

Algebraic Geometry · Mathematics 2025-02-13 Tsung-Chen Chen , Hui-Wen Lin , Sz-Sheng Wang

We consider the set of forms of a toric variety over an arbitrary field: those varieties which become isomorphic to a toric variety after base field extension. In contrast to most previous work, we also consider arbitrary isomorphisms…

Algebraic Geometry · Mathematics 2016-10-04 Alexander Duncan

We initiate the study of the resolution of singularities properties of Nash blowups over fields of prime characteristic. We prove that the iteration of normalized Nash blowups desingularizes normal toric surfaces. We also introduce a prime…

Algebraic Geometry · Mathematics 2023-04-07 Daniel Duarte , Jack Jeffries , Luis Núñez-Betancourt

We develop a theory of multi-stage degenerations of toric varieties over finite rank valuation rings, extending the Mumford--Gubler theory in rank one. Such degenerations are constructed from fan-like structures over totally ordered abelian…

Algebraic Geometry · Mathematics 2018-05-16 Tyler Foster , Dhruv Ranganathan

A flag variety is a homogenous variety $G/B$ where $G$ is a simple algebraic group over the complex numbers and $B$ is a Boel subgroup of $G$. A Schubert variety $X_w$ is a subvariety of $G/B$ indexed by an element $w$ in the Weyl group of…

Algebraic Geometry · Mathematics 2023-11-21 Eunjeong Lee , Mikiya Masuda , Seonjeong Park

We introduce the notion of cracked polytope, and - making use of joint work with Coates and Kasprzyk - construct the associated toric variety $X$ as a subvariety of a non-singular toric variety $Y$ under certain conditions. Restricting to…

Algebraic Geometry · Mathematics 2019-10-14 Thomas Prince

Our main goal is to show that the Gelfand--Tsetlin toric degeneration of the type A flag variety can be obtained within a degenerate representation-theoretic framework similar to the theory of PBW degenerations. In fact, we provide such…

Representation Theory · Mathematics 2020-10-07 Igor Makhlin

We give a complete description of the cohomology ring $A^*(\overline Z)$ of a compactification of a linear subvariety $Z$ of a torus in a smooth toric variety whose fan $\Sigma$ is supported on the tropicalization of $Z$. It turns out that…

Algebraic Geometry · Mathematics 2016-12-01 Andreas Gross

We present a proof of embedded desingularization for closed subschemes which does not make use of Hilbert-Samuel function and avoids Hironaka's notion of normal flatness. This proof, already sketched in [A course on constructive…

Algebraic Geometry · Mathematics 2007-05-23 S. Encinas , O. Villamayor

We will describe a one-step "Gorensteinization" process for a Schubert variety by blowing-up along its boundary divisor. The local question involves Kazhdan-Lusztig varieties which can be degenerated to affine toric schemes defined using…

Algebraic Geometry · Mathematics 2019-08-20 Sergio Da Silva

We describe a practical and effective method for reconstructing the deformation class of a Fano manifold X from a Laurent polynomial f that corresponds to X under Mirror Symmetry. We explore connections to nef partitions, the smoothing of…

Algebraic Geometry · Mathematics 2021-12-17 Tom Coates , Alexander Kasprzyk , Thomas Prince

The first steps in defining tropicalization for spherical varieties have been taken in the last few years. There are two parts to this theory: tropicalizing subvarieties of homogeneous spaces and tropicalizing their closures in spherical…

Algebraic Geometry · Mathematics 2018-02-22 Evan D. Nash

Given a spherical homogeneous space G/H of minimal rank, we provide a simple procedure to describe its embeddings as varieties with torus action in terms of divisorial fans. The torus in question is obtained as the identity component of the…

Algebraic Geometry · Mathematics 2015-06-16 Klaus Altmann , Valentina Kiritchenko , Lars Petersen

The GIT chamber decomposition arising from a subtorus action on a quasiprojective toric variety is a polyhedral complex. Denote by Sigma the fan that is the cone over the polyhedral complex. In this paper we show that the toric variety…

Algebraic Geometry · Mathematics 2007-05-23 Alastair Craw , Diane Maclagan

Given a singular hypersurface in a regular 2-dimensional scheme essentially of finite type over a field, we construct an embedded resolution of singularities by weighted blow-ups. This differs from our earlier work which required…

Algebraic Geometry · Mathematics 2026-05-12 Dan Abramovich , Ming Hao Quek , Bernd Schober

Let $Z$ be an affine algebraic variety and $X$ be a smooth flexible variety. We develop some criteria under which $Z$ admits a closed embedding into $X$. In particular, we show that if $X$ is isomorphic (as an algebraic variety) to a…

Algebraic Geometry · Mathematics 2023-07-04 Shulim Kaliman