Journal of Operator Theory, Vol. 58, No. 2 (Fall 2007), pp. 415-440 (26 pages) In this paper the well-known result that a definitizable operator in a Krein space remains definitizable after a finite ...

Adjoint linear transformations between Hilbert spaces or, more generally, between dual systems of topological vector spaces induce contravariant functors which are adjoint on the right-essentially a ...

We also prove that the two sets of Maxwell equations only depend on the non-linear elations of the conformal group of ...