English
Related papers

Related papers: K-stability of Casagrande-Druel varieties

200 papers

We study the probability that an $(n - m)$-dimensional linear subspace in $\mathbb{P}^n$ or a collection of points spanning such a linear subspace is contained in an $m$-dimensional variety $Y \subset \mathbb{P}^n$. This involves a strategy…

Algebraic Geometry · Mathematics 2022-04-26 Soohyun Park

We classify the d-dimensional simplicial, terminal, and reflexive polytopes with at least 3d-2 vertices. In particular, it turns out that these are all smooth Fano polytopes. This improves on previous results of Casagrande in 2006 and Oebro…

Algebraic Geometry · Mathematics 2015-07-31 Benjamin Assarf , Michael Joswig , Andreas Paffenholz

We construct proper moduli algebraic spaces of K-polystable $\mathbb{Q}$-Fano cones (a.k.a. Calabi-Yau cones) or equivalently their links i.e., Sasaki-Einstein manifolds with singularities. As a byproduct, it gives alternative algebraic…

Algebraic Geometry · Mathematics 2024-08-13 Yuji Odaka

We construct degenerations of Mukai varieties and linear sections thereof to special unobstructed Fano Stanley-Reisner schemes corresponding to convex deltahedra. This can be used to find toric degenerations of rank one index one Fano…

Algebraic Geometry · Mathematics 2019-11-26 Jan Arthur Christophersen , Nathan Owen Ilten

We construct smooth varieties admitting small contractions from arbitrary smooth projective varieties. This construction generalizes Kawamata's four-dimensional example. We also give sufficient conditions for divisors on these varieties to…

Algebraic Geometry · Mathematics 2026-01-21 Yuto Masamura , Tomoki Yoshida

We prove K-stability for infinitely many smooth members of the family 2.19 of the Mukai-Mori classification.

Algebraic Geometry · Mathematics 2024-12-25 Tiago Duarte Guerreiro , Luca Giovenzana , Nivedita Viswanathan

Firstly, we see that the bases of the miniversal deformations of isolated $\mathbb{Q}$-Gorenstein toric singularities are quite restricted. In particular, we classify the analytic germs of embedding dimension $\leq 2$ which are the bases of…

Algebraic Geometry · Mathematics 2022-09-13 Andrea Petracci

We provide a sufficient condition for polarisations of Fano varieties to be K-stable in terms of Tian's alpha invariant, which uses the log canonical threshold to measure singularities of divisors in the linear system associated to the…

Algebraic Geometry · Mathematics 2016-04-21 Ruadhaí Dervan

In this paper, we prove that for a threefold of Fano type $X$ and a movable $\mathbb{Q}$-Cartier Weil divisor $D$ on $X$, the number of smooth varieties that arise during the running of a $D$-MMP is bounded by $1 + h^1(X, 2D)$.…

Algebraic Geometry · Mathematics 2025-11-13 Donghyeon Kim

We identify Le Potier's moduli spaces of limit stable pairs $(F,s)$, where $F$ is a 2-dimensional sheaf on a nonsingular projective 4-fold $X$ and $s \in H^0(F)$, with the moduli spaces of polynomial stable 2-term complexes in derived…

Algebraic Geometry · Mathematics 2021-11-16 Amin Gholampour , Yunfeng Jiang , Jason Lo

We show relationships between uniform K-stability and plt blowups of log Fano pairs. We see that it is enough to evaluate certain invariants defined by volume functions for all plt blowups in order to test uniform K-stability of log Fano…

Algebraic Geometry · Mathematics 2019-07-17 Kento Fujita

Extending previous results, we prove that for $n \ge 5$ all hypersurfaces of degree $n+1$ in ${\mathbb P}^{n+1}$ with isolated ordinary double points are birational superrigid and K-stable, hence admit a weak K\"ahler--Einstein metric.

Algebraic Geometry · Mathematics 2022-01-19 Tommaso de Fernex

We consider Fano manifolds admitting an algebraic torus action with general orbit of codimension one. Using a recent result of Datar and Szekelyhidi, we effectively determine the existence of Kahler-Ricci solitons for those manifolds via…

Algebraic Geometry · Mathematics 2022-05-20 Nathan Ilten , Hendrik Süß

We study weighted Fano fourfolds of K3 type realized as hypersurfaces in weighted projective spaces. Under the additional assumption that the singular locus has dimension at most one, we prove that only finitely many such families exist. We…

Algebraic Geometry · Mathematics 2025-06-24 Valeria Bertini , Francesco Antonio Denisi , Enrico Fatighenti , Annalisa Grossi

In this paper we prove that any smooth prime Fano threefold, different from the Mukai-Umemura threefold, contains a 1-dimensional family of intersecting lines. Combined with a result of the second author (see J. Algebr. Geom. 8:2 (1999),…

Algebraic Geometry · Mathematics 2007-05-23 Atanas Iliev , Carmen Schuhmann

We classify three-dimensional nodal Fano varieties that are double covers of smooth quadrics branched over intersections with quartics acted on by finite simple non-abelian groups, and study their rationality.

Algebraic Geometry · Mathematics 2018-08-07 Victor Przyjalkowski , Constantin Shramov

Motivated by the problem for the existence of K\"ahler-Einstein edge metrics, Cheltsov and Rubinstein conjectured the K-polystability of asymptotically log Fano varieties with small cone angles when the anti-log-canonical divisors are not…

Algebraic Geometry · Mathematics 2019-07-12 Kento Fujita

The first secant variety $\Sigma$ of a rational normal curve of degree $d \geq 3$ is known to be a $\mathbf{Q}$-Fano threefold. In this paper, we prove that $\Sigma$ is K-polystable, and hence, $\Sigma$ admits a weak K\"{a}hler-Einstein…

Algebraic Geometry · Mathematics 2023-11-23 In-Kyun Kim , Jinhyung Park , Joonyeong Won

We explore connections between existence of $\Bbbk$-rational points for Fano varieties defined over $\Bbbk$, a subfield of $\mathbb{C}$, and existence of K\"ahler-Einstein metrics on their geometric models. First, we show that geometric…

Algebraic Geometry · Mathematics 2024-11-04 Hamid Abban , Ivan Cheltsov , Takashi Kishimoto , Frederic Mangolte

We study K-stability properties of a smooth Fano variety X using non-Archimedean geometry, specifically the Berkovich analytification of X with respect to the trivial absolute value on the ground field. More precisely, we view…

Algebraic Geometry · Mathematics 2018-05-30 Sébastien Boucksom , Mattias Jonsson