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Concepts of a quantum information theory of many letters

Kim J. Bostroem
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Abstract

A theoretical framework is presented allowing the treatment of quantum messages with components of variable length. To this aim a many-letter space, similiar to the Fock space, is constructed, generalizing the standard quantum information theory of block messages of fixed length. In the many-letter space a length operator can be defined measuring the length of a quantum message, whose eigenspaces are the block Hilbert spaces used in the standard theory.

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Kim J. Bostroem. 2000-09-20. Concepts of a quantum information theory of many letters. https://arxiv.org/abs/quant-ph/0009052

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