English
Related papers

Related papers: Affine lines in the complement of a smooth plane c…

200 papers

Using Weil descent, we give bounds for the number of rational points on two families of curves over finite fields with a large abelian group of automorphisms: Artin-Schreier curves of the form $y^q-y=f(x)$ with $f\in\Fqr[x]$, on which the…

Algebraic Geometry · Mathematics 2010-05-28 Antonio Rojas-Leon

Nonsingular plane curves over a finite field $\mathbb{F}_q$ of degree $q+2$ passing through all the $\mathbb{F}_q$-points of the plane admita representation by $3\times 3$ matrices over $\mathbb{F}_q$. We classify their degenerations by…

Algebraic Geometry · Mathematics 2019-06-18 Masaaki Homma

In this article, we study isomorphisms between complements of irreducible curves in the projective plane $\mathbb{P}^2$, over an arbitrary algebraically closed field. Of particular interest are rational unicuspidal curves. We prove that if…

Algebraic Geometry · Mathematics 2023-06-22 Mattias Hemmig

We settle the automorphism groups of curves appearing in a classification list of smooth plane curves with at least two Galois points. One of them is an ordinary curve whose automorphism group exceeds the Hurwitz bound.

Algebraic Geometry · Mathematics 2014-11-13 Satoru Fukasawa

We classify all finite subgroups of the plane Cremona group which have a fixed point. In other words, we determine all rational surfaces X with an action of a finite group G such that X is equivariantly birational to a surface which has a…

Algebraic Geometry · Mathematics 2016-01-05 Igor Dolgachev , Alexander Duncan

A plane curve is called strange if its tangent line at any smooth point passes through a fixed point, called the strange point. In this paper, we study $\mathbb{A}^1$-curves on the complement of a rational strange curve of degree $p$ in…

Algebraic Geometry · Mathematics 2021-08-23 Qile Chen , Ryan Contreras

Let $A$ be an abelian variety over an algebraically closed field. We show that $A$ is the automorphism group scheme of some smooth projective variety if and only if $A$ has only finitely many automorphisms as an algebraic group. This…

Algebraic Geometry · Mathematics 2021-05-24 Jérémy Blanc , Michel Brion

Let $f$ be an endomorphism of the projective line. There is a natural conjugation action on the space of such morphisms by elements of the projective linear group. The group of automorphisms, or stabilizer group, of a given $f$ for this…

Dynamical Systems · Mathematics 2021-06-14 Brandon Gontmacher , Benjamin Hutz , Grayson Jorgenson , Srinjoy Srimani , Simon Xu

Let $\Bbbk$ be a perfect field with algebraic closure $\overline{\Bbbk}$. If $H$ is a subgroup of plane automorphisms over $\Bbbk$ and $p\in\overline{\Bbbk}^2$ is a point, we describe the subgroup consisting of plane automorphisms which…

Algebraic Geometry · Mathematics 2022-11-08 Iván Pan , Alvaro Rittatore

Let Y be a smooth del Pezzo surface of degree 3 polarized by a very ample divisor that is not proportional to the anticanonical one. Then the affine cone over Y is flexible in codimension one. Equivalently, such a cone has an open subset…

Algebraic Geometry · Mathematics 2024-04-18 Alexander Perepechko

A proof of freeness of the commutator subgroup of the fundamental group of a smooth irreducible affine curve over a countable algebraically closed field of nonzero characteristic. A description of the abelianizations of the fundamental…

Algebraic Geometry · Mathematics 2007-05-23 Manish Kumar

Let k be an algebraically closed field of characteristic zero, F its algebraically closed extension, and G be the group of k-automorphisms of F endowed with a natural topology. One of the purposes of this paper is to show that any…

Representation Theory · Mathematics 2009-04-07 M. Rovinsky

Let $X$ be a smooth projective algebraic curve of genus $g\geq 2$ defined over a field $K$. We show that $X$ can be defined over its field of moduli if it has odd signature, i.e. if the signature of the covering $X\to X/\Aut(X)$ is of type…

Algebraic Geometry · Mathematics 2012-07-06 Michela Artebani , Saúl Quispe

We study the affine cone over a reducible nodal curve $X$ obtained by gluing three projective lines along three pairs of points to form a connected curve of arithmetic genus \(1\). We endow \(X\) with a line bundle \(L\) of multidegree…

Algebraic Geometry · Mathematics 2025-12-16 Mounir Nisse

We classify all possible automorphism groups of smooth cubic surfaces over an algebraically closed field of arbitrary characteristic. As an intermediate step we also classify automorphism groups of quartic del Pezzo surfaces. We show that…

Algebraic Geometry · Mathematics 2018-10-15 Igor Dolgachev , Alexander Duncan

Let $k$ be an algebraically closed field of positive characteristic $p>0$ and $C \to {\mathbb P}^1_k$ a $p$-cyclic cover of the projective line ramified in exactly one point. We are interested in the $p$-part of the full automorphism group…

Algebraic Geometry · Mathematics 2007-05-23 Claus Lehr , Michel Matignon

We study the set $R$ of nonplanar rational curves of degree $d<q+2$ on a smooth Hermitian surface $X$ of degree $q+1$ defined over an algebraically closed field of characteristic $p>0$, where $q$ is a power of $p$. We prove that $R$ is the…

Algebraic Geometry · Mathematics 2019-05-28 Norifumi Ojiro

We obtain some general restrictions on the continuous endomorphisms of a profinite group G under the assumption that G has only finitely many open subgroups of each index (an assumption which automatically holds, for instance, if G is…

Group Theory · Mathematics 2011-12-19 Colin D. Reid

This note is a supplement to the papers: R. V. Gurjar, K. Masuda, M. Miyanishi and P. Russell, Affine lines on affine surfaces and the Makar-Limanov invariant, preprint, 2005, 42p. and T. Kishimoto and H. Kojima, Affine lines on {\bf…

Algebraic Geometry · Mathematics 2007-05-23 Mikhail Zaidenberg

We introduce the class of rational plane curves parameterizable by conics as an extension of the family of curves parameterizable by lines (also known as monoid curves). We show that they are the image of monoid curves via suitable…

Algebraic Geometry · Mathematics 2012-10-04 Teresa Cortadellas Benitez , Carlos D'Andrea
‹ Prev 1 3 4 5 6 7 10 Next ›