TY - JOUR
T1 - Past of a particle in an entangled state
AU - Paneru, Dilip
AU - Cohen, Eliahu
PY - 2017/12/22
Y1 - 2017/12/22
N2 - Vaidman has proposed a controversial criterion for determining the past of a single quantum particle based on the “weak trace” it leaves. We here consider more general examples of entangled systems and analyze the past of single, as well as pairs of entangled pre- and postselected particles. Systems with nontrivial time evolution are also analyzed. We argue that in these cases, examining only the single-particle weak trace provides information which is insufficient for understanding the system as a whole. We therefore suggest to examine, alongside with the past of single particles, also the past of pairs, triplets and eventually the entire system, including higher-order, multipartite traces in the analysis. This resonates with a recently proposed top-down approach by Aharonov, Cohen and Tollaksen for understanding the structure of correlations in pre- and postselected systems.
AB - Vaidman has proposed a controversial criterion for determining the past of a single quantum particle based on the “weak trace” it leaves. We here consider more general examples of entangled systems and analyze the past of single, as well as pairs of entangled pre- and postselected particles. Systems with nontrivial time evolution are also analyzed. We argue that in these cases, examining only the single-particle weak trace provides information which is insufficient for understanding the system as a whole. We therefore suggest to examine, alongside with the past of single particles, also the past of pairs, triplets and eventually the entire system, including higher-order, multipartite traces in the analysis. This resonates with a recently proposed top-down approach by Aharonov, Cohen and Tollaksen for understanding the structure of correlations in pre- and postselected systems.
KW - entanglement
KW - Past of a quantum particle
KW - quantum nonlocality
KW - weak values
UR - http://www.scopus.com/inward/record.url?scp=85039151236&partnerID=8YFLogxK
U2 - 10.1142/S0219749917400196
DO - 10.1142/S0219749917400196
M3 - Article (Academic Journal)
AN - SCOPUS:85039151236
VL - 15
JO - International Journal of Quantum Information
JF - International Journal of Quantum Information
SN - 0219-7499
M1 - 1740019
ER -