EntityQ3555169· pop 9· linked from 137 articlesnull vectorSign in to savevector that is annihilated by a quadratic formConnectionsquadratic formEntitymathematicsEntityInternational Standard Book NumberEntitycomplex numberEntityreal numberEntityspacetimeEntityvector spaceEntityimaginary unitEntityCambridge University PressEntitybasisEntityMinkowski spacetimeEntitylinear independenceEntityAnatoly FomenkoEntityorthogonalityEntityEmil ArtinEntitySergei NovikovEntityLie algebraEntitybilinear formEntityLeonard Eugene DicksonEntitysplit-complex numberEntityCategoriesLinear algebraQuadratic forms