A Note on Block Sequences in Hilbert Spaces
نویسندگان
چکیده
Abstract. Block sequences with respect to frames in Hilbert spaces have been defined. Examples have been provided to show that a block sequence with respect to a given frame may not even be a Bessel sequence. Also, a necessary and sufficient condition under which a block sequence with respect to a frame is a frame has been given. Further, applications of block sequences to obtain Fusion frames and Fusion frame systems have been given. Finally, a problem has been posed and observed that an affirmative answer to this problem gives an affirmative answer to the Feichtinger Conjecture.
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