فرخنده تخته

Let H be a separable Hilbert space, and let gB be the set of all g-Bessel sequences for H. We show that gB is a C^*-algebra isometrically isomorphic to L(H) (the algebra of all bounded linear operators of H). Also, we classify g-Bessel sequences in H in terms of different kinds of operators in L(H). Using operator theory tools, we investigate geometry of g-Bessel sequences.