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Related papers: Some remarks on log surfaces

200 papers

Let f : X -> S be any elliptic fibration. If X has dimension 3 and is not uniruled, then X has a minimal model (with terminal singularities) [Mori]. In earlier work we have shown that there exists a birationally equivalent elliptic…

alg-geom · Mathematics 2008-02-03 A. Grassi

In this paper we characterize logarithmic surfaces which admit K\"ahler-Einstein metrics with negative scalar curvature and small edge singularities along a normal crossing divisor.

Differential Geometry · Mathematics 2014-10-10 Luca Fabrizio Di Cerbo

Drawing on the theory of Minimal Model Program singularities for foliations, we define relative canonical and log-canonical singularities for algebraic stacks with finite generic stabilisers. We show that if a point has log-canonical…

Algebraic Geometry · Mathematics 2026-03-27 Federico Bongiorno

Let $(X,D)$ be an open log del Pezzo surface of rank one, that is, $X$ is a normal projective surface of Picard rank one, the boundary $D$ is a reduced nonzero divisor on $X$, and the anti-log canonical divisor $-(K_X+D)$ is ample. We show…

Algebraic Geometry · Mathematics 2025-08-20 Karol Palka , Tomasz Pełka

We classify all projective surfaces with only T-singularities, ample canonical class, and $K^2=2p_g-4$. In this way, we identify all surfaces, smoothable or not, with only T-singularities in the Koll\'ar--Shepherd-Barron--Alexeev (KSBA)…

Algebraic Geometry · Mathematics 2025-07-09 Vicente Monreal , Jaime Negrete , Giancarlo Urzúa

In this article we study polynomial logarithmic $q$-forms on a projective space and characterize those that define singular foliations of codimension $q$. Our main result is the algebraic proof of their infinitesimal stability when $q=2$…

Algebraic Geometry · Mathematics 2019-02-20 Javier Gargiulo Acea

In this paper, we investigate the relationship of F-regular (resp. F-pure) rings and log terminal (resp. log canonical) singularities. Also, we extend the notions of F-regularity and F-purity to "F-singularities of pairs." The notions of…

Algebraic Geometry · Mathematics 2007-05-23 Nobuo Hara , Kei-ichi Watanabe

In this paper, we generalize the finiteness of models theorem in [BCHM06] to Kawamata log terminal pairs with fixed Kodaira dimension. As a consequence, we prove that a Kawamata log terminal pair with $\mathbb{R}-$boundary has a canonical…

Algebraic Geometry · Mathematics 2020-05-08 Junpeng Jiao

In this note a proof is given for global existence and uniqueness of minimal surfaces of Lorentzian type from a cylinder into globally hyperbolic Lorentzian manifolds for given initial values up to the first derivatives.

Differential Geometry · Mathematics 2016-05-20 Olaf Müller

We prove an existence theorem for good moduli spaces, and use it to construct the second flip in the log minimal model program for the moduli space of stable curves. In fact, our methods give a uniform, self-contained construction of the…

Algebraic Geometry · Mathematics 2014-10-07 Jarod Alper , Maksym Fedorchuk , David Ishii Smyth , Frederick van der Wyck

For a birational analogue of minimal elliptic surfaces X/Y, the singularities of the fibers define a log structure in codimension one on Y. Via base change, we have a log structure in codimension one on Y', for any birational model Y' of Y.…

Algebraic Geometry · Mathematics 2007-05-23 Florin Ambro

We show that to every maximal surface with conelike singularities in Lorentz-Minkowski space $\mathbb{L}^3$ that can be locally represented as the graph of a smooth function, there exists a corresponding timelike minimal surface in…

Differential Geometry · Mathematics 2019-09-18 Aryaman Patel

We prove existence of flips, special termination, the base point free theorem and, in the case of log general type, the existence of minimal models for F-dlt foliated pairs of co-rank one on a $\mathbb Q$-factorial projective threefold. As…

Algebraic Geometry · Mathematics 2025-09-05 Paolo Cascini , Calum Spicer

Solenoids induced by split sequences are introduced, as the inverse limit object of a sequence of fold maps. The topology of a solenoid is explored, and it is established that solenoids have naturally arising singular foliated structures.…

Dynamical Systems · Mathematics 2025-04-09 Sarasi Jayasekara

In the recent paper \cite{DGNP} we have proved that the only stable $C^2$ minimal surfaces in the first Heisenberg group $\Hn$ which are graphs over some plane and have empty characteristic locus must be vertical planes. This result…

Differential Geometry · Mathematics 2009-03-26 Donatella Danielli , Nicola Garofalo , Duy-Minh Nhieu , Scott Pauls

This is an expanded version of our work [AN88], 1988, in Russian. We classify del Pezzo surfaces over C with log terminal singularities of index \le 2. By classification, we understand a description of the intersection graph of all…

Algebraic Geometry · Mathematics 2007-05-23 Valery Alexeev , Viacheslav V. Nikulin

We develop a general theory of log spaces, in which one can make sense of the basic notions of logarithmic geometry, in the sense of Fontaine-Illusie-Kato. Many of our general constructions with log spaces are new, even in the algebraic…

Differential Geometry · Mathematics 2015-07-27 W. D. Gillam , Samouil Molcho

In this paper, we study noncommutative surface singularities arising from orders. The singularities we study are mild in the sense that they have finite representation type or, equivalently, are log terminal in the sense of the Mori minimal…

Rings and Algebras · Mathematics 2020-06-16 Daniel Chan , Colin Ingalls

In this article we prove a finiteness result on the number of log minimal models for $3$-folds in char $p>5$. We then use this result to prove a version of Batyrev's conjecture on the structure of nef cone of curves on $3$-folds in…

Algebraic Geometry · Mathematics 2018-09-17 Omprokash Das

For a class of functions (called minimal Rad\'o functions) that arise naturally in minimal surface theory, we bound the number of interior critical points (counting multiplicity) in terms of the boundary data and the Euler characteristic of…

Differential Geometry · Mathematics 2023-06-22 David Hoffman , Francisco Martín , Brian White