6533b86ffe1ef96bd12ce005

RESEARCH PRODUCT

Lower Semi-frames, Frames, and Metric Operators

Camillo TrapaniJ.-p. AntoineRosario Corso

subject

Pure mathematicsGeneral Mathematics010102 general mathematicsFrame (networking)Hilbert spacelower semi-framesWeakly measurable functionFunction (mathematics)01 natural sciencesDomain (mathematical analysis)Parseval's theoremFramessymbols.namesakeOperator (computer programming)Settore MAT/05 - Analisi Matematica0103 physical sciencesMetric (mathematics)symbolsmetric operators0101 mathematics010306 general physicsMathematics

description

AbstractThis paper deals with the possibility of transforming a weakly measurable function in a Hilbert space into a continuous frame by a metric operator, i.e., a strictly positive self-adjoint operator. A necessary condition is that the domain of the analysis operator associated with the function be dense. The study is done also with the help of the generalized frame operator associated with a weakly measurable function, which has better properties than the usual frame operator. A special attention is given to lower semi-frames: indeed, if the domain of the analysis operator is dense, then a lower semi-frame can be transformed into a Parseval frame with a (special) metric operator.

https://doi.org/10.1007/s00009-020-01652-x