3 citations · 5 across the 12 of their papers we have counts for
13 papers
On Orthogonal Graphs and their Automorphisms
Hans Cuypers
We provide a characterization of the connected subgraphs of the graphs with vertex set the non-isotropic points in a quadratic space , two points adjacent if and only if the…
Dynamical Lie algebras generated by Pauli strings and quadratic spaces over
Hans Cuypers
Dynamical Lie algebras, i.e. Lie subalgebras of , generated by Pauli strings have recently been studied intensively. They are also called Pauli Lie algebras or…
Graphs, Axial Algebras and their Automorphism Groups
Hans Cuypers
We introduce a class of algebras over a field related to directed graphs in which all edges are labeled by nonzero elements of the field . If all labels ar…
Characterizations of symplectic polar spaces
Ilaria Cardinali, Hans Cuypers, Luca Giuzzi +1
A polar space S is said to be symplectic if it admits an embedding e in a projective geometry PG(V) such that the e-image e(S) of S is defined by an alternating form of V. In this…
A geometric characterization of the finitary special linear and unitary Lie algebras
Hans Cuypers, Marc Oostendorp
An extremal element in a Lie algebra is an element for which the space is contained in the linear span of . Long root elements in cla…
Line graphs of Multi-Graphs and the forbidden graph
Hans Cuypers
The line graph of a multi-graph is the graph whose vertices are the edges of , where two such edges are adjacent if and only if they meet in a single vertex of . We p…
Whitney's Theorem for Line Graphs of Multi-Graphs
Hans Cuypers
Whitney's Theorem states that every graph, different from or , is uniquely determined by its line graph. A -line graph of a multi-graph is the graph with as verti…
Quasi-Clifford algebras, Quadratic forms over , and Lie Algebras
Hans Cuypers
Let be a graph, whose vertices are colored black and white and labeled with invertible elements from a commutative and associ…
The geometry of hyperbolic lines in polar spaces
Hans Cuypers
In this paper we consider partial linear spaces induced on the point set of a polar space, but with as lines the hyperbolic lines of this polar space. We give some geometric charac…
On some subgroups of linear groups over generated by elements of order
Hans Cuypers
Let be a vector space over the field of order . We investigate subgroups of the linear group which are generated by a conjugacy class of elements of order su…
A geometric characterization of the symplectic Lie algebra
Hans Cuypers, Yael Fleischmann
A nonzero element in a Lie algebra with Lie product is called extremal if is a multiple of for all . In this paper we characterize the…
A geometric characterization of the classical Lie algebras
Hans Cuypers, Yael Fleischmann
A nonzero element x in a Lie algebra g over a field F with Lie product [ , ] is called a extremal element if [x, [x, g]] is contained in Fx. Long root elements in classical Lie alg…
Recovering the Lie algebra from its extremal geometry
Hans Cuypers, Kieran Roberts, Sergey Shpectorov
An element of a Lie algebra over the field is extremal if . Under minor assumptions, it is known that, for a simple Lie algebra , the extremal geometry…