Rieuwert J. Blok
Extensions of isomorphisms for affine dual polar spaces and strong parapolar spaces
Let B be a class of point-line geometries. Given
?i ? B with subspace
i for
i = 1, 2, does any isomorphism ?1 ?
1 ? ?2 ?
2 extend to a unique isomorphism ?1
? ?2? It is known to be true if B is the class of almost all projective spaces or the class
of almost all nondegenerate polar spaces. We show that this is true for the class
of almost all strong parapolar spaces, including dual polar
spaces.
A special case occurs when ?1 = ?2 = ? has an
embedding into a projective space ?(V ) that is natural in
the sense that Aut(? ) ? P?L(V ). Then the question
becomes whether ?(V ) is also the natural embedding for
? ?
. Our result shows that in most cases the stabilizer
StabAut(?)(? ?
) is faithful on
? ?
and equals Aut(? ?
) and so the
answer is affirmative. We know that there exist some interesting exceptions. These
will be covered in a subsequent paper.
Advances in Geometry, Walter de Gruyter
Print ISSN: 1615-715X
Volume: 5, 10/2005
Seiten: 509 - 532
Zum Artikel (extern)
Alle verfügbaren Artikel dieser Zeitschrift anzeigen