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Related papers: Block-Transitive Designs in Affine Spaces

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A q-design with parameters t-(v,k,lambda_t)_q is a pair (V, B) of the v-dimensional vector space V over GF(q) and a collection B of k-dimensional subspaces of V, such that each t-dimensional subspace of V is contained in precisely lambda_t…

Combinatorics · Mathematics 2015-10-01 Maarten De Boeck , Anamari Nakic

In this article, we investigate symmetric 2-designs of prime order admitting a flag-transitive automorphism group G. Recently, the authors proved that the automorphism group G of this type of designs must be point-primitive, and is of…

Group Theory · Mathematics 2023-07-26 Z. W. Lu , S. L. Zhou

Let $\mathcal{D} = (\mathcal{P}, \mathcal{B})$ be a $2$-$(v, k, \lambda)$ design, and let $G$ be a half-flag-transitive automorphism group of ${\cal D}$. In this article, we first establish three sufficient conditions for $G$ to be…

Group Theory · Mathematics 2025-09-29 Xiaoqin Zhan

We introduce a new type of $n$-dimensional generalization of symmetric $(v,k,\lambda)$ block designs. We prove upper bounds on the dimension $n$ in terms of $v$ and $k$. We also define the corresponding concept of $n$-dimensional difference…

Combinatorics · Mathematics 2025-04-10 Vedran Krčadinac , Lucija Relić

In this article, we study symmetric $(v, k, \lambda)$ designs admitting a flag-transitive and point-primitive automorphism group $G$ whose socle $X$ is a finite simple exceptional group of Lie type. We prove a reduction theorem, severely…

Group Theory · Mathematics 2020-08-27 Seyed Hassan Alavi , Mohsen Bayat , Ashraf Daneshkhah

In this note we survey recent results on automorphisms of affine algebraic varieties, infinitely transitive group actions and flexibility. We present related constructions and examples, and discuss geometric applications and open problems.

Algebraic Geometry · Mathematics 2013-07-18 I. Arzhantsev , H. Flenner , S. Kaliman , F. Kutzschebauch , M. Zaidenberg

Given an integer $k\ge3$ and a group $G$ of odd order, if there exists a $2$-$(v,k,1)$-design and if $v$ is sufficiently large, then there is such a design whose automorphism group has a subgroup isomorphic to $G$. A weaker result is proved…

Combinatorics · Mathematics 2021-03-24 William M. Kantor

We survey recent results on multiple transitivity of automorphism groups of affine algebraic varieties. We consider the property of infinite transitivity of the special automorphism group, which is equivalent to flexibility of the…

Algebraic Geometry · Mathematics 2023-04-04 Ivan Arzhantsev

Given an STS(v), we ask if there is a permutation of the points of the design such that no $\ell$ consecutive points in this permutation contain a block of the design. Results are obtained in the cases $\ell = 3,4$.

Combinatorics · Mathematics 2019-02-15 Donald L. Kreher , Douglas R. Stinson

In this article, we investigate symmetric $(v,k,\lambda)$ designs $\mathcal{D}$ with $\lambda$ prime admitting flag-transitive and point-primitive automorphism groups $G$. We prove that if $G$ is an almost simple group with socle a finite…

Group Theory · Mathematics 2020-09-14 Seyed Hassan Alavi , Mohsen Bayat , Ashraf Daneshkhah

The classification of the $2$-designs with $\lambda=2$ admitting a flag-transitive automorphism groups with socle $PSL(2,q)$ is completed by settling the two open cases in \cite{ABDT}. The result is achieved by using conics and hyperovals…

Combinatorics · Mathematics 2024-05-01 Alessandro Montinaro , Yanwei Zhao , Zhilin Zhang , Shenglin Zhou

This paper computes the graded automorphism group of quantum affine spaces. Specifically, we determine that this group is isomorphic to a semi-direct product of a blocked diagonal matrix group and a permutation group.

Quantum Algebra · Mathematics 2025-02-17 Hai Jin

In this paper, we construct new families of flag-transitive linear spaces with $q^{2n}$ points and $q^{2}$ points on each line that admit a one-dimensional affine automorphism group. We achieve this by building a natural connection with…

Combinatorics · Mathematics 2021-08-10 Tao Feng , Jianbing Lu

Let $\mathcal{D}=\left(\mathcal{P},\mathcal{B} \right)$ be a symmetric $2$-$(v,k,\lambda )$ design admitting a flag-transitive, point-imprimitive automorphism group $G$ that leaves invariant a non-trivial partition $\Sigma$ of…

Combinatorics · Mathematics 2022-06-15 Alessandro Montinaro

A notion of $t$-designs in the symmetric group on $n$ letters was introduced by Godsil in 1988. In particular $t$-transitive sets of permutations form a $t$-design. We derive special lower bounds for $t=1$ and $t=2$ by a power moment…

Combinatorics · Mathematics 2023-06-27 Minjia Shi , XiaoXiao Li , Patrick Solé

Let $\mathcal{D}$ be a non-trivial quasi-symmetric $2$-design with two block intersection numbers $x=0$ and $2\leq y\leq10$, and suppose that $G$ is an automorphism group of $\mathcal{D}$. If $G$ is flag-transitive and point-primitive, then…

Combinatorics · Mathematics 2025-06-13 Jianbing Lu

In this paper we determine the at least $4$-dimensional affine reductive homogeneous manifolds for an at most $9$-dimensional simple Lie group or an at most $6$-dimensional semi-simple Lie group. Those reductive spaces among them which…

Differential Geometry · Mathematics 2015-06-30 Ágota Figula

We give a construction of a family of designs with a specified point-partition, and determine the subgroup of automorphisms leaving invariant the point-partition. We give necessary and sufficient conditions for a design in the family to…

Combinatorics · Mathematics 2015-02-25 Peter J. Cameron , Cheryl E. Praeger

In this paper, we consider the existence of group divisible designs (GDDs) with block size $4$ and group sizes $4$ and $7$. We show that there exists a 4-GDD of type $4^t 7^s$ for all but a finite specified set of feasible values for $(t,…

Combinatorics · Mathematics 2024-01-23 R. Julian R. Abel , Thomas Britz , Yudhistira A. Bunjamin , Diana Combe

Affine structures on a Lie groupoid, including affine $k$-vector fields, $k$-forms and $(p,q)$-tensors are studied. We show that the space of affine structures is a 2-vector space over the space of multiplicative structures. Moreover, the…

Differential Geometry · Mathematics 2021-02-09 Honglei Lang , Zhangju Liu , Yunhe Sheng