Document Type : Research Paper


1 Department of Mathematics, Faculty of Science, University of Qom, Qom, Iran

2 Faculty of Mathematical Sciences and Computer, Kharazmi University, Tehran, Iran


In this paper we get some results and applications for duals and approximate duals of g-frames in Hilbert spaces. In particular, we consider the stability of duals and approximate duals under bounded operators and we study duals and approximate duals of g-frames in the direct sum of Hilbert spaces. We also obtain some results for perturbations of approximate duals.


Main Subjects

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