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AIP conference proceedings

Decomposition of non-composite quantum systems

Додин Дмитрий Валерьевич, I. G. Kovalenko, Alexander I. Lvovsky

Published Jan 1, 2009• 0 citations

Abstract

A composite quantum system is a fundamental object in quantum informatics. A composite quantum system is considered a system whose dimension is a composite integer number whereas the prime integers may only correspond to non‐composite systems. Entanglement and the procedure of reduction to a subsystem via averaging over environment are only formulated for composite systems. In the present report we introduce a procedure of decomposition into ‘subsystems’ for a system whose dimension is an arbitrary number including a prime integer. This procedure generalizes the standard procedure of reduction. In the particular case of a non‐composite system the space of states of the decomposed system splits into direct sum of subspaces of states and the average dimension of subspaces is a fractional number. We compare the properties of the introduced procedure of decomposition and the standard separation into subsystems.

DOI: 10.1063/1.3131390

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