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Related papers: K-stability of Casagrande-Druel varieties

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We define the relative stability threshold of a family of Fano varieties over a DVR and show that it is computed by a divisorial valuation. In the case when the special fiber is K-unstable, but the generic fiber is K-semistable, we use the…

Algebraic Geometry · Mathematics 2025-10-08 Harold Blum , Yuchen Liu , Chenyang Xu , Ziquan Zhuang

We prove that K-polystable degenerations of Q-Fano varieties are unique. Furthermore, we show that the moduli stack of K-stable Q-Fano varieties is separated. Together with [Jia17,BL18], the latter result yields a separated Deligne-Mumford…

Algebraic Geometry · Mathematics 2019-07-10 Harold Blum , Chenyang Xu

We develop a general approach to prove K-stability of Fano varieties. The new theory is used to (a) prove the existence of K\"ahler-Einstein metrics on all smooth Fano hypersurfaces of Fano index two, (b) to compute the stability thresholds…

Algebraic Geometry · Mathematics 2022-06-15 Hamid Abban , Ziquan Zhuang

In this note, we study K-stability of smooth Fano threefolds that can be obtained by blowing up the three-dimensional projective space along a smooth elliptic curve of degree five.

Algebraic Geometry · Mathematics 2024-07-09 Ivan Cheltsov , Piotr Pokora

We find all K-polystable smooth Fano threefolds that can be obtained as blowup of projective space along the disjoint union of a twisted cubic curve and a line.

Algebraic Geometry · Mathematics 2022-03-25 Elena Denisova

This four-pages note is an invitation to explore explicit K-stability for arbitrary K\"ahler classes of low dimension and low rank spherical varieties. We apply our simple combinatorial criterion of K-stability of rank one spherical…

Algebraic Geometry · Mathematics 2024-08-26 Thibaut Delcroix

Tian's criterion for K-stability states that a Fano variety of dimension $n$ whose alpha invariant is greater than $\frac{n}{n+1}$ is K-stable. We show that this criterion is sharp by constructing singular Fano varieties with alpha…

Algebraic Geometry · Mathematics 2020-08-06 Yuchen Liu , Ziquan Zhuang

We prove K-stability of smooth Fano 3-folds of Picard rank 3 and degree 20 that satisfy very explicit generality condition.

Algebraic Geometry · Mathematics 2024-03-15 Elena Denisova

Ross and Thomas introduced the concept of slope stability to study K-stability, which has conjectural relation with the existence of constant scalar curvature K\"ahler metric. This paper presents a study of slope stability of Fano manifolds…

Algebraic Geometry · Mathematics 2014-02-26 Jun-Muk Hwang , Hosung Kim , Yongnam Lee , Jihun Park

In this short note we show the unboundedness of the dimension of the K-moduli space of $n$-dimensional Fano varieties, and that the dimension of the stack can also be unbounded while, simultaneously, the dimension of the corresponding…

Algebraic Geometry · Mathematics 2021-01-15 Jesus Martinez-Garcia , Cristiano Spotti

It is shown that any, possibly singular, Fano variety X admitting a Kahler-Einstein metric is K-polystable, thus confirming one direction of the Yau-Tian-Donaldson conjecture in the setting of Q-Fano varieties equipped with their…

Differential Geometry · Mathematics 2015-06-10 Robert J. Berman

We study the K-stability of $\mathbb{Q}$-Fano spherical varieties using compatible divisors. More precisely, if the $\mathbb{Q}$-Fano variety, with a reductive group action, has an open Borel subgroup orbit, then there is a unique…

Algebraic Geometry · Mathematics 2026-01-05 Renpeng Zheng

General hyperplane sections of a Fano threefold $Y$ of index 2 and Picard rank 1 are del Pezzo surfaces, and their Picard group is related to a root system. To the corresponding roots, we associate objects in the Kuznetsov component of $Y$…

Algebraic Geometry · Mathematics 2025-08-06 Matteo Altavilla , Marin Petkovic , Franco Rota

We find Fano threefolds $X$ admitting K\"ahler-Ricci solitons (KRS) with non-trivial moduli, which are $\mathbb{T}$-varieties of complexity two. More precisely, we show that the weighted K-stability of $(X,\xi_0)$ (where $\xi_0$ is the…

Algebraic Geometry · Mathematics 2025-08-01 Minghao Miao , Linsheng Wang

We develop a framework to study the K-stability of weighted Fano hypersurfaces based on a combination of birational and convex-geometric techniques. As an application, we prove that all quasi-smooth weighted Fano hypersurfaces of index 1…

Algebraic Geometry · Mathematics 2026-01-07 Livia Campo , Kento Fujita , Taro Sano , Luca Tasin

Let $X$ be a cubic threefold, quartic double solid or Gushel--Mukai threefold, and $\mathcal{K}u(X)\subset \mathrm{D}^b(X)$ be its Kuznetsov component. We show that a stability condition $\sigma$ on $\mathcal{K}u(X)$ is Serre-invariant if…

Algebraic Geometry · Mathematics 2023-10-27 Changping Fan , Zhiyu Liu , Songtao Kenneth Ma

The moduli space of bundle stable pairs $\overline{M}_C(2,\Lambda)$ on a smooth projective curve $C$, introduced by Thaddeus, is a smooth Fano variety of Picard rank two. Focusing on the genus two case, we show that its K-moduli space is…

Algebraic Geometry · Mathematics 2026-01-29 Junyan Zhao

In this paper we consider double covers of the projective space in relation with the problem of extensions of varieties, specifically of extensions of canonical curves to $K3$ surfaces and Fano 3-folds. In particular we consider $K3$…

Algebraic Geometry · Mathematics 2022-05-17 Ciro Ciliberto , Thomas Dedieu

By the description due to Mukai and Iliev, a smooth prime Fano threefold X of genus 9 is associated to a surface P(V), ruled over a smooth plane quartic Gamma. We use Kuznetsov's integral functor to study rank-2 stable sheaves on X with odd…

Algebraic Geometry · Mathematics 2014-11-03 Maria Chiara Brambilla , Daniele Faenzi

In this paper, we study the K-stability of polarized spherical varieties. After reduction, it can be treated as a variational problem of the reduced functional of the Futaki invariant on the associated moment polytope. With the convexity…

Differential Geometry · Mathematics 2022-01-17 Yan Li , Bin Zhou