English
Related papers

Related papers: Del Pezzo foliations with log canonical singularit…

200 papers

We introduce a class of noncommutative surfaces called Artin--Schelter surfaces of del Pezzo types, which contains del Pezzo surfaces as special cases. We show that the moduli stacks of marked Artin--Schelter surfaces of del Pezzo types are…

Algebraic Geometry · Mathematics 2025-08-08 Shinnosuke Okawa , Kazushi Ueda

In this paper, we prove that if a $3$-dimensional quasi-projective variety $X$ over an algebraically closed field of characteristic $p>3$ has only log canonical singularities, then so does a general hyperplane section $H$ of $X$. We also…

Algebraic Geometry · Mathematics 2025-09-17 Kenta Sato

We consider relatively minimal fibrations of curves of genus two on rational surfaces whose Picard numbers are not maximal. By birational morphisms, such fibred surfaces are interpreted as pencils of plane curves. We show that only four are…

Algebraic Geometry · Mathematics 2010-06-24 Shinya Kitagawa

In this paper, we classify Du Val del Pezzo surfaces of Picard rank one in characteristic two and three. We also show that if a Du Val del Pezzo surface is Frobenius split, then a general anti-canonical member is smooth. Furthermore, in…

Algebraic Geometry · Mathematics 2023-10-26 Tatsuro Kawakami , Masaru Nagaoka

We consider singular holomorphic foliations on compact complex surfaces with invariant rational nodal curve of positive self-intersection. Then, under some assumptions, we list all possible foliations.

Dynamical Systems · Mathematics 2016-06-27 Edileno de Almeida Santos

We investigate a geometric criterion for a smooth curve $C$ of genus $14$ and degree $18$ to be described as the zero locus of sections in an Ulrich bundle of rank $3$ on a del Pezzo threefold $V_5 \subset \mathbb{P}^6$. The main challenge…

Algebraic Geometry · Mathematics 2026-01-01 Marian Aprodu , Yeongrak Kim

It is known that the set of log canonical thresholds (lcts) on any varieties with fixed dimension satisfies the ascending chain condition. Inspired by the foliated minimal model program, it is intriguing to study the foliated version of…

Algebraic Geometry · Mathematics 2025-11-13 Yen-An Chen

We prove the irreducibility of the spaces of rational curves on del Pezzo manifolds of Picard rank 1 and dimension at least 4 by analyzing the fibers of evaluation maps. As a corollary, we prove Geometric Manin's Conjecture in these cases.

Algebraic Geometry · Mathematics 2024-04-10 Fumiya Okamura

We show that smooth quintic del Pezzo threefolds over arbitrary base schemes are classified by non-degenerate ternary symmetric bilinear forms. Then we describe the automorphism group schemes, the Hilbert schemes of lines and the orbit…

Algebraic Geometry · Mathematics 2025-11-20 Tetsushi Ito , Akihiro Kanemitsu , Teppei Takamatsu , Yuuji Tanaka

The "canonical dimension" of an algebraic group over a field by definition is the maximum of the canonical dimensions of principal homogenous spaces under that group. Over a field of characteristic zero, we prove that the canonical…

Algebraic Geometry · Mathematics 2007-05-23 Jean-Louis Colliot-Thélène , Nikita A. Karpenko , Alexander S. Merkurjev

In this paper we consider the classification of singularities (Du Val) and real structures (Wall) of weak Del Pezzo surfaces from an algorithmic point of view. It is well known that the singularities of weak Del Pezzo surfaces correspond to…

Algebraic Geometry · Mathematics 2021-03-09 Niels Lubbes

We give a complete answer for the existence of Kawamata type semiorthogonal decompositions of derived categories of nodal del Pezzo threefolds. More precisely, we show that nodal del Pezzo threefolds of degree $1\leq d \leq 4$ have no…

Algebraic Geometry · Mathematics 2024-12-30 Nebojsa Pavic , Evgeny Shinder

Third-order symmetric Lorentzian manifolds, i.e. Lorentzian manifold with zero third derivative of the curvature tensor, are classified. These manifolds are exhausted by a special type of pp-waves, they generalize Cahen-Wallach spaces and…

Differential Geometry · Mathematics 2018-08-21 Anton S. Galaev

In this paper we classify codimension 1 Mukai foliations on complex projective manifolds

Algebraic Geometry · Mathematics 2014-04-21 Carolina Araujo , Stéphane Druel

Let X be a K3 surface with an involution g which has non-empty fixed locus X^g and acts non-trivially on a non-zero holomorphic 2-form. We shall construct all such pairs (X, g) in a canonical way, from some better known double coverings of…

Algebraic Geometry · Mathematics 2007-05-23 D. -Q. Zhang

We introduce the notion of strongly asymptotically log del Pezzo flags, and classify such flags under the assumption that their zero-dimensional part lies in the boundary. We use this result to give a new and conceptual proof of the…

Algebraic Geometry · Mathematics 2024-11-20 Yanir A. Rubinstein

We classify all complex surfaces with quotient singularities that do not contain any smooth rational curves, under the assumption that the canonical divisor of the surface is not pseudo-effective. As a corollary we show that if $X$ is a log…

Algebraic Geometry · Mathematics 2018-10-17 Ziquan Zhuang

This paper reviews Lacini's classification [Lac24] of log del Pezzo surfaces of rank one in characteristics different from two and three, with a focus on where and how Lacini enhanced the techniques of Keel and McKernan [KM99]. We point out…

Algebraic Geometry · Mathematics 2025-12-16 Masaru Nagaoka

Let X be a smooth, complex Fano 4-fold, and rho(X) its Picard number. If X contains a prime divisor D with rho(X)-rho(D)>2, then either X is a product of del Pezzo surfaces, or rho(X)=5 or 6. In this setting, we completely classify the case…

Algebraic Geometry · Mathematics 2020-07-23 Cinzia Casagrande , Eleonora A. Romano

We construct motivic cohomology cycles in the group $H^3_{\mathcal M}(Z,{\mathbb Q}(2))$ where $Z$ is a K3 surface obtained as a double cover of a del Pezzo surface $X$ branched at a curve in $|-2K_X|$. The construction uses (-1) curves on…

Algebraic Geometry · Mathematics 2024-11-07 Ramesh Sreekantan