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Related papers: Fano threefolds with infinite automorphism groups

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We prove that the outer automorphism group $\mathrm{Out}(N)$ of an infinitely generated free nilpotent group $N$ of class two is complete.

Group Theory · Mathematics 2025-05-20 Vladimir A. Tolstykh

We compute explicitly the automorphism and outer automorphism group of all large-type free-of-infinity Artin groups. Our strategy involves reconstructing the associated Deligne complexes in a purely algebraic manner, i.e. in a way that is…

Group Theory · Mathematics 2024-10-15 Nicolas Vaskou

In this paper we look at the automorphisms of the multiplicative group of finite nearfields. We find partial results for the actual automorphism groups. We find counting techniques for the size of all finite nearfields. We then show that…

Rings and Algebras · Mathematics 2016-02-02 Tim Boykett , Karin-Therese Howell

We show that klt Fano varieties and certain lc Fano varieties contain free higher-genus curves in their smooth loci. Our methods also allow us to find free curves on varieties in positive characteristic and on quasiprojective varieties,…

Algebraic Geometry · Mathematics 2026-01-09 Eric Jovinelly , Brian Lehmann , Eric Riedl

We study the Picard variety of the Fano surface of nodal and mildly cuspidal cubic threefolds in arbitrary characteristic by relating divisors on the Fano surface to divisors on the symmetric product of a curve of genus 4.

Algebraic Geometry · Mathematics 2010-10-12 Gerard van der Geer , Alexis Kouvidakis

We study the automorphism group of an idempotent evolution algebra, show that any finite group can be the automorphism group of an evolution algebra, and describe certain evolution algebras with given automorphism groups. In particular, we…

Rings and Algebras · Mathematics 2022-02-15 Songpon Sriwongsa , Yi Ming Zou

We prove that a weak $\mathbb{Q}$-Fano $3$-fold with terminal singularities has unobstructed deformations. By using this result and computing some invariants of a terminal singularity, we provide two results on global deformation of a weak…

Algebraic Geometry · Mathematics 2017-09-12 Taro Sano

We prove that the Klein cubic threefold $F$ is the only smooth cubic threefold which has an automorphism of order 11. We compute the period lattice of the intermediate Jacobian of $F$ and study its Fano surface $S$. We compute also the set…

Algebraic Geometry · Mathematics 2010-01-28 Xavier Roulleau

In this paper we explain the complete biregular classification of all 4-dimensional smooth toric Fano varieties. The main result states that there exist exactly 123 different types of toric Fano 4-folds up to isomorphism.

Algebraic Geometry · Mathematics 2007-05-23 Victor V. Batyrev

We find sharp upper bounds on the order of the automorphism group of a hypersurface in complex projective space in every dimension and degree. In each case, we prove that the hypersurface realizing the upper bound is unique up to…

Algebraic Geometry · Mathematics 2024-11-28 Louis Esser , Jennifer Li

We give a necessary and sufficient condition for a generalized Bott manifold to be Fano or weak Fano. As a consequence we characterize Fano Bott manifolds.

Algebraic Geometry · Mathematics 2018-11-16 Yusuke Suyama

We study unirationality and rationality of Fano threefolds of degree 18 over nonclosed fields.

Algebraic Geometry · Mathematics 2019-10-31 Brendan Hassett , Yuri Tschinkel

We study degree of irrationality of quasismooth anticanonically embedded weighted Fano 3-fold hypersurfaces that have terminal singularities.

Algebraic Geometry · Mathematics 2022-10-27 Ivan Cheltsov , Jihun Park

The classification of toric Fano manifolds with large Picard number corresponds to the classification of smooth Fano polytopes with large number of vertices. A smooth Fano polytope is a polytope that contains the origin in its interior such…

Algebraic Geometry · Mathematics 2015-08-11 Benjamin Assarf , Benjamin Nill

We introduce an extension of the (tame) polynomial automorphism group over finite fields: the profinite (tame) polynomial automorphism group, which is obtained by putting a natural topology on the automorphism group. We show that most known…

Algebraic Geometry · Mathematics 2015-07-13 Stefan Maubach , Abdul Rauf

We obtain 866 isomorphism classes of five-dimensional nonsingular toric Fano varieties using a computer program and the database of four-dimensional reflexive polytopes. The algorithm is based on the existence of facets of Fano polytopes…

Algebraic Geometry · Mathematics 2010-02-14 Maximilian Kreuzer , Benjamin Nill

We prove that Fano 5-folds with nef tangent bundles are rational homogeneous manifolds.

Algebraic Geometry · Mathematics 2015-03-17 Akihiro Kanemitsu

Let $M$ be a smooth Fano threefold such that a canonical extension of the tangent bundle is an affine manifold. We show that $M$ is rational homogeneous.

Algebraic Geometry · Mathematics 2022-11-22 Andreas Höring , Thomas Peternell

The homology groups of the automorphism group of a free group are known to stabilize as the number of generators of the free group goes to infinity, and this paper relativizes this result to a family of groups that can be defined in terms…

Geometric Topology · Mathematics 2014-11-11 Allen Hatcher , Nathalie Wahl

A smooth cuboid can be identified with a $3\times 3$ matrix of linear forms, with coefficients in a field $K$, whose determinant describes a smooth cubic in the projective plane. To each such matrix one can associate a group scheme over…

Group Theory · Mathematics 2025-04-23 Joshua Maglione , Mima Stanojkovski