On semi-inner product spaces, II
On the approximation of continuosly diffentialble functions in Hilbert spaces
On the Definition of a Quadratic Form
On the Definition of Hilbert Space.
On the dependence of the orthogonal projector on deformations of the scalar product
We consider scalar products on a given Hilbert space parametrized by bounded positive and invertible operators defined on this space, and orthogonal projectors onto a fixed closed subspace of the initial Hilbert space corresponding to these scalar products. We show that the projector is an analytic function of the scalar product, we give the explicit formula for its Taylor expansion, and we prove some algebraic formulas for projectors.
On the homotopical classification of DJ-mappings of infnitely dimensional spheres
On the Lebesgue decomposition of Gleason measures
On the ordered sets in -dimensional real inner product spaces.
On the products of quantum logics
On the Stability of the Functional Quadratic on A-orthogonal Vectors
Original title unknown
Original title unknown