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Related papers: DW(6,n), n>2, has no ovoid: A single proof

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We provide new proofs for the non-existence of ovoids in hyperbolic spaces of rank at least four in even characteristic, and for the Hermitian polar space $\mathsf{H}(5, 4)$. We also improve the results of A. Klein on the non-existence of…

Combinatorics · Mathematics 2015-09-17 John Bamberg , Jan De Beule , Ferdinand Ihringer

In this paper we develop non-existence results for $m$-ovoids in the classical polar spaces $Q^-(2r+1,q), W(2r-1,q)$ and $H(2r,q^2)$ for $r>2$. In [4] a lower bound on $m$ for the existence of $m$-ovoids of $H(4,q^2)$ is found by using the…

Combinatorics · Mathematics 2024-02-21 Jan De Beule , Jonathan Mannaert , Valentino Smaldore

In this paper we are concerned with $m$-ovoids of the symplectic polar space ${\cal W}(2n+1, q)$, $q$ even. In particular we show the existence of an elliptic quadric of ${\rm PG}(2n+1, q)$ not polarizing to ${\cal W}(2n+1, q)$ forming a…

Combinatorics · Mathematics 2022-07-05 Michela Ceria , Francesco Pavese

We investigate what we call generalized ovoids, that is families of totally isotropic subspaces of finite classical polar spaces such that each maximal totally isotropic subspace contains precisely one member of that family. This is a…

Combinatorics · Mathematics 2024-01-22 Jozefien D'haeseleer , Ferdinand Ihringer , Kai-Uwe Schmidt

We give a computer-based proof for the non-existence of distance-$2$ ovoids in the dual split Cayley hexagon $\mathsf{H}(4)^D$. Furthermore, we give upper bounds on partial distance-$2$ ovoids of $\mathsf{H}(q)^D$ for $q \in \{2, 4\}$.

Combinatorics · Mathematics 2016-06-24 Anurag Bishnoi , Ferdinand Ihringer

In this paper we provide constructive lower bounds on the sizes of the largest partial ovoids of the symplectic polar spaces ${\cal W}(3, q)$, $q$ odd square, $q \not\equiv 0 \pmod{3}$, ${\cal W}(5, q)$ and of the Hermitian polar spaces…

Combinatorics · Mathematics 2022-03-10 Michela Ceria , Jan De Beule , Francesco Pavese , Valentino Smaldore

An $m$-ovoid of a finite polar space $\mathcal{P}$ is a set $\mathcal{O}$ of points such that every maximal subspace of $\mathcal{P}$ contains exactly $m$ points of $\mathcal{O}$. In the case when $\mathcal{P}$ is an elliptic quadric…

Combinatorics · Mathematics 2021-11-16 Alexander L. Gavrilyuk , Klaus Metsch , Francesco Pavese

We use the representation $T_2(O)$ for $\q(4,q)$ to show that maximal partial ovoids of $\q(4,q)$ of size $q^2-1$, $q=p^h$, $p$ odd prime, $h > 1$, do not exist. Although this was known before, we give a slightly alternative proof, also…

Combinatorics · Mathematics 2012-03-09 Jan De Beule

In [9], the codewords of small weight in the dual code of the code of points and lines of Q(4, q) are characterised. Inspired by this result, using geometrical arguments, we characterise the codewords of small weight in the dual code of the…

Combinatorics · Mathematics 2012-01-17 Valentina Pepe , Leo Storme , Geertrui Van de Voorde

We generalise the work of Segre (1965), Cameron - Goethals - Seidel (1978), and Vanhove (2011) by showing that nontrivial $m$-ovoids of the dual polar spaces $DQ(2d, q)$, $DW(2d-1,q)$ and $DH(2d-1,q^2)$ ($d\ge 3$) are hemisystems. We also…

Combinatorics · Mathematics 2017-05-16 John Bamberg , Jesse Lansdown , Melissa Lee

We prove that, given a partition of the point-set of $PG(3,q), q=2^n >2$, by ovoids $\{\theta_i\}^q_{i=0}$ of $PG(3,q)$ and a line $\ell$ of $PG(3,q)$, not tangent to $\theta_0$ if $\ell^\perp$ denotes the polar of $\ell$ relative to the…

Group Theory · Mathematics 2017-04-21 N. S. Narasimha Sastry , R. P. Shukla

In this paper we show that n-dimensional dual hyperovals cannot exist in all but one classical polar space of rank n if n is even. This resolves a question posed by Yoshiara.

Combinatorics · Mathematics 2015-04-17 John Sheekey

The Desarguesian ovoids in the orthogonal polar space $Q^+(7,q)$ with $q$ even have first been introduced by Kantor by examining the $8$-dimensional absolutely irreducible modular representations of $\text{PGL}(2,q^3)$. We investigate this…

Information Theory · Computer Science 2022-08-30 Tao Feng , Michael Kiermaier , Peixian Lin , Kai-Uwe Schmidt

In this paper, we develop a new method for constructing $m$-ovoids in the symplectic polar space $\W(2r-1,\q)$ from some strongly regular Cayley graphs in \cite{Brouwer1999Journal}. Using this method, we obtain many new $m$-ovoids which can…

Combinatorics · Mathematics 2019-09-18 Tao Feng , Ye Wang , Qing Xiang

The main aim of this interdisciplinary paper is to characterize all maps on finite Minkowski space of arbitrary dimension $n$ that map pairs of distinct light-like events into pairs of distinct light-like events. Neither bijectivity of maps…

Mathematical Physics · Physics 2017-01-10 Marko Orel

The geometry of the real four-qubit Pauli group, being embodied in the structure of the symplectic polar space W(7,2), is analyzed in terms of ovoids of a hyperbolic quadric of PG(7,2), the seven-dimensional projective space of order two.…

Mathematical Physics · Physics 2012-07-13 Metod Saniga , Peter Levay , Petr Pracna

A generalised hexagon of order $(s,t)$ is said to be \emph{extremal} if $t$ meets the Haemers-Roos bound, that is, $t=s^3$. The \emph{dual twisted triality hexagons} associated to the exceptional Lie type groups $\,^3D_4(s)$ have these…

Combinatorics · Mathematics 2014-05-22 John Bamberg

In this paper, we complete the classification of transitive ovoids of finite Hermitian polar spaces.

Combinatorics · Mathematics 2020-11-19 Tao Feng , Weicong Li

Ovoids of the non-degenerate quadric Q(4,q) of PG(4,q) have been studied since the end of the '80s. They are rare objects and, beside the classical example given by an elliptic quadric, only three classes are known for q odd, one class for…

Combinatorics · Mathematics 2022-03-29 Daniele Bartoli , Nicola Durante

Let V be a quadratic space with a form q over an arbitrary local field F of characteristic different from 2. Let $W=V \oplus Fe$ with the form Q extending q with Q(e)=1. Consider the standard embedding of O(V) into O(W) and the two-sided…

Representation Theory · Mathematics 2009-05-17 Avraham Aizenbud , Dmitry Gourevitch , Eitan Sayag
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