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The Two-State Vector Formalism of Qauntum Mechanics: an Updated Review

Yakir Aharonov·Lev Vaidman
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Abstract

In this paper we present the two-state vector formalism of quantum mechanics. It is a time-symmetrized approach to standard quantum theory particularly helpful for the analysis of experiments performed on pre- and post-selected ensembles. Several peculiar effects which naturally arise in this approach are considered. In particular, the concept of ``weak measurements'' (standard measurements with weakening of the interaction) is discussed in depth revealing a very unusual but consistent picture. Also, a design of a gedanken experiment which implements a kind of quantum ``time machine'' is described. The issue of time-symmetry in the context of the two-state vector formalism is clarified.

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Yakir Aharonov, Lev Vaidman. 2007-06-10. The Two-State Vector Formalism of Qauntum Mechanics: an Updated Review. https://arxiv.org/abs/quant-ph/0105101

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