CIEM   05476
CENTRO DE INVESTIGACION Y ESTUDIOS DE MATEMATICA
Unidad Ejecutora - UE
artículos
Título:
Generalized quadrangles and subconstituent algebra
Autor/es:
F. LEVSTEIN; C. MALDONADO
Revista:
CUBO
Editorial:
Departamento de Matemática, Universidade Federal de Pernambuco
Referencias:
Lugar: Recife-PE.; Año: 2008
ISSN:
0716-7776
Resumen:
The point graph of a generalized quadrangle $GQ(s,t)$ is astrongly regular graph $Gamma=srg( u,kappa, lambda, mu)$whose parameters depend on $s$ and $t$. By a detailed analysis ofthe adjacency matrix  we compute the Terwilliger algebra of thiskind of graphs (and denoted it by $mathcal{T}$). We find that there are only two non-isomorphicTerwilliger  algebras  for all the generalized quadrangles. Thetwo classes correspond to wether  $s^2=t$ or not. We decompose thealgebra into direct sum of simple ideals. Considering the action$mathcal{T} imes mathbb{C}^X longrightarrow mathbb{C}^X$ wefind the decomposition into irreducible $mathcal{T}$-submodulesof $mathbb{C}^X$ (where $X$ is the set of vertices of the$Gamma$).