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arXiv:1405.3483 · Physical Review A

Quantum mechanics without state vectors

Steven Weinberg

Published Oct 2, 2014• 56 citations
arXivHTMLPDF

Abstract

A proposal is formulated to give up the description of physical states in terms of ensembles of state vectors and to rely only on density matrices instead, which opens up a variety of new ways for density matrices to transform under various symmetries different from the unitary symmetries of ordinary quantum mechanics.
DOI
10.1103/physreva.90.042102

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