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Related papers: Some remarks on Fano threefolds of index two and s…

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We prove K-stability of smooth Fano 3-folds of Picard rank 3 and degree 22 that satisfy very explicit generality condition.

Algebraic Geometry · Mathematics 2024-01-08 Ivan Cheltsov

We prove that any vector bundle computing the rank-two Clifford index of a smooth projective algebraic curve is linearly semistable. We also identify conditions under which such bundles become linearly stable, thereby addressing a question…

Algebraic Geometry · Mathematics 2025-09-11 Ali Bajravani , Angela Ortega

We define a one-dimensional family of "Euler" stability conditions on $\mathbb{P}^n$ which are conjectured to converge to Gieseker stability for coherent sheaves. Here, we focus on ${\mathbb P}^3$, first identifying Euler stability…

Algebraic Geometry · Mathematics 2022-01-03 Dapeng Mu

We study the conormal sheaves and singular schemes of 1-dimensional foliations on smooth projective varieties $X$ of dimension 3 and Picard rank 1. We prove that if the singular scheme has dimension 0, then the conormal sheaf is…

Algebraic Geometry · Mathematics 2021-08-03 Alana Cavalcante , Marcos Jardim , Danilo Santiago

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

We obtain a classification of a Q-factorial Q-Fano 3-fold $X$ with the following properties: the Picard number of $X$ is 1; the Gorenstein index of $X$ is 2; the Fano index of $X$ is 1/2; $h^0 (-K_X) \geq 4$; there exists an index 2 point…

Algebraic Geometry · Mathematics 2016-09-07 Hiromichi Takagi

An object in the bounded derived category D^b(Coh(X)) of coherent sheaves on a complex projective K3 surface X is spherical if it is rigid and simple. Although spherical objects form only a discrete set in the moduli stack of complexes,…

Algebraic Geometry · Mathematics 2013-09-12 Daniel Huybrechts

For three-dimensional piecewise-smooth systems of ordinary differential equations, this paper characterises the stability of points that belong to a switching surface and are equilibria of exactly one of the two neighbouring pieces of the…

Dynamical Systems · Mathematics 2026-02-10 David J. W. Simpson

We prove the $K$-polystability of all smooth complex Fano threefolds admitting an effective action of $\text{SL}_2$ but not of a 2-torus or 3-torus. In particular, the existence of K\"{a}hler-Einstein metrics on varieties in the families…

Algebraic Geometry · Mathematics 2022-01-12 Jack Rogers

We study K-stability of smooth Fano threefolds of Picard rank $2$ and degree $22$ which can be obtained by blowing up a smooth complete intersection of two quadrics in $\mathbb{P}^5$ along a conic. We also describe the automorphism groups…

We show that a Fano manifold (X,-K_X) is not slope stable with respect to a smooth curve Z if and only if (X,Z) is isomorphic to one of (projective space, line), (product of projective line and projective space, fiber of second projection)…

Algebraic Geometry · Mathematics 2011-07-08 Kento Fujita

We prove that every projectively normal Fano manifold in $\mathbb{P}^{n+r}$ of index $1$, codimension $r$ and dimension $n\geq 10r$ is birationally superrigid and K-stable. This result was previously proved by Zhuang under the complete…

Algebraic Geometry · Mathematics 2019-11-28 Fumiaki Suzuki

In this article, we systematically investigate the stability properties of certain warped product Einstein manifolds. We characterize stability of these metrics in terms of an eigenvalue condition of the Einstein operator on the base…

Differential Geometry · Mathematics 2017-06-08 Klaus Kroencke

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 prove that the deformations of a smooth complex Fano threefold X with Picard number 1, index 1, and degree 10, are unobstructed. The differential of the period map has two-dimensional kernel. We construct two two-dimensional components…

Algebraic Geometry · Mathematics 2008-12-22 O. Debarre , A. Iliev , L. Manivel

Let $X$ be any smooth prime Fano threefold of degree $2g-2$ in $\mathbb{P}^{g+1}$, with $g \in \{3,\ldots,10,12\}$. We prove that for any integer $d$ satisfying $\left\lfloor \frac{g+3}{2} \right\rfloor \leq d \leq g+3$ the Hilbert scheme…

Algebraic Geometry · Mathematics 2022-06-22 Ciro Ciliberto , Flaminio Flamini , Andreas Leopold Knutsen

A variety is said to satisfy Condition (A) if every finite abelian subgroup of its automorphism group has a fixed point. We show that a smooth Fano 3-fold not satisfying Condition (A) is K-polystable unless it is contained in eight…

Algebraic Geometry · Mathematics 2025-05-08 Hamid Abban , Ivan Cheltsov , Takashi Kishimoto , Frederic Mangolte

Let S be a K3 surface and S^[n] the Hilbert scheme of length n subschemes of S. Over the cartesian square of S^[n] there exists a natural reflexive rank 2n-2 coherent sheaf E, which is locally free away from the diagonal. The fiber of E,…

Algebraic Geometry · Mathematics 2017-05-09 Eyal Markman

We study the Hilbert scheme $\mathcal{H}$ of twisted cubics on a special smooth Gushel-Mukai threefolds $X_{10}$. We show that it is a smooth irreducible projective threefold if $X_{10}$ is general among special Gushel-Mukai threefolds,…

Algebraic Geometry · Mathematics 2021-08-30 Shizhuo Zhang

We study GIT stability of divisors in products of projective spaces. We first construct a finite set of one-parameter subgroups sufficient to determine the stability of the GIT quotient. In addition, we characterise all maximal orbits of…

Algebraic Geometry · Mathematics 2023-12-07 Ioannis Karagiorgis , Theresa A. Ortscheidt , Theodoros S. Papazachariou