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Related papers: On some Fano--Enriques threefolds

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We classify smooth Fano manifolds X with the Picard number $\rho_X \geq 3$ such that there exists an extremal ray which has a birational contraction that maps a divisor to a point.

Algebraic Geometry · Mathematics 2012-12-21 Kento Fujita

Let $X$ be a smooth complete Fano variety over $\mathbb{C}$. We show that the Cox ring $\bigoplus_{L\in\text{Pic}(X)}H^0(X,\mathcal{O}_X(L))$ is Gorenstein with canonical singularities.

Algebraic Geometry · Mathematics 2012-02-20 Morgan V. Brown

We study Fano threefolds with~terminal singularities admitting a "minimal" action of a finite group. We prove that under certain additional assumptions such a variety does not contain planes. We also obtain an upper bounds of the number of…

Algebraic Geometry · Mathematics 2019-08-14 Yuri Prokhorov

We study smoothings of Fano threefolds. We prove that the Picard number remains constant in the case of terminal Gorenstein singularities.

Algebraic Geometry · Mathematics 2007-05-23 Priska Jahnke , Ivo Radloff

We classify Q-factorial Gorenstein Fano non-degenerate complete intersection threefolds in fake weighted projective spaces.

Algebraic Geometry · Mathematics 2025-10-14 Juergen Hausen , Paul Weiss

We explicitly fully describe the K-moduli space of Fano threefold family number 3.3. We first show that K-semistable Fano varieties with volume greater than 18 are Gorenstein canonical and admit general elephants, decreasing the bound on a…

Algebraic Geometry · Mathematics 2025-10-16 Erroxe Etxabarri-Alberdi , James Matthew Jones , Theodoros Stylianos Papazachariou

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 study the pencils of minimal degree on the smooth curves lying on a K3 surface X which carries a fixed-point free involution. Generically, the gonality of these curves is totally governed by the genus 1 fibrations of X

Algebraic Geometry · Mathematics 2019-07-30 Marco Ramponi

In this paper we show that a general element of $|-K_X|$ on a four-dimensional Fano manifold has at most terminal singularities. We then determine an explicit local expression of these singular points.

Algebraic Geometry · Mathematics 2015-05-12 Liana Heuberger

A V_{12} Fano threefold is a smooth Fano threefold X of index 1 with Pic X = Z and (-K_X)^3=12. We show that the bounded derived category of coherent sheaves on any V_{12} threefold X admits a semiorthogonal decomposition consisting of two…

Algebraic Geometry · Mathematics 2007-05-23 Alexander Kuznetsov

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

Let $X$ be a smooth complex projective rationally connected threefold with $-K_X$ nef and not semi-ample. In our previous work, we classified all such threefolds when $|{-}K_X|$ has no fixed divisor. In this paper, we continue our…

Algebraic Geometry · Mathematics 2023-01-24 Zhixin Xie

We show that certain Galois covers of K-semistable Fano varieties are K-stable. We use this to give some new examples of Fano manifolds admitting K\"ahler-Einstein metrics, including hypersurfaces, double solids and threefolds.

Algebraic Geometry · Mathematics 2018-05-16 Ruadhaí Dervan

We show exceptionality of certain families of non-quasismooth weighted hypersurfaces. In particular these admit K\"ahler-Einstein metrics. Our examples are produced by the monomials generating the complex deformations of orbifolds whose…

Algebraic Geometry · Mathematics 2026-02-17 Jaime Cuadros Valle , Joe Lope Vicente

In this paper we study Fano threefolds with a torsion divisor (Fano--Enriques). Due to this torsion divisor, they can be described as quotients of Fano threefolds by a finite abelian group action. We start from lists of Fano threefolds by…

Algebraic Geometry · Mathematics 2007-05-23 Jorge Caravantes

We study the deformation theory of a Fano variety X with normal crossing singularities of dimension at most three. We obtain a formula for the sheaf T^1(X) of first order deformations of X in a suitable log resolution of X and its singular…

Algebraic Geometry · Mathematics 2009-07-22 Nikolaos Tziolas

Let X be a Q-factorial Gorenstein Fano variety. Suppose that the singularities of X are canonical and that the locus where they are non-terminal has dimension zero. Let D be a prime divisor of X. We show that rho_X - rho_D < 9 (where rho is…

Algebraic Geometry · Mathematics 2012-12-05 Gloria Della Noce

For an embedded Fano manifold $X$, we introduce a new invariant $S_X$ related to the dimension of covering linear spaces. The aim of this paper is to classify Fano manifolds $X$ which have large $S_X$.

Algebraic Geometry · Mathematics 2017-06-20 Taku Suzuki

We prove that the Fano variety of lines of a cuspidal cyclic cubic fourfold is a symplectic variety with transversal A2-singularities and we study the properties of the nonsymplectic order three automorphism induced by the covering…

Algebraic Geometry · Mathematics 2023-03-28 Samuel Boissiere , Tobias Heckel , Alessandra Sarti

This paper obtains criteria for a Fano variety X with normal crossing singularities defined over an algebraically closed field of characteristic zero, to be smoothable. The difference with the original version is that the theory of…

Algebraic Geometry · Mathematics 2013-07-09 Nikolaos Tziolas