Unification of spatiotemporal quantum formalisms: mapping between process and pseudo-density matrices via multiple-time states

Liu, Xiangjing1,2; Jia, Zhian3,4; Qiu, Yixian3; Li, Fei1,2; Dahlsten, Oscar2,5,6

2024-03-01

10.1088/1367-2630/ad264c

NEW JOURNAL OF PHYSICS   影响因子和分区

1367-2630

We consider the relation between three different approaches to defining quantum states across several times and locations: the pseudo-density matrix (PDM), the process matrix, and the multiple-time state approaches. Previous studies have shown that bipartite two-time states can reproduce the statistics of bipartite process matrices. Here, we show that the operational scenarios underlying two-time states can be represented as PDMs, and thereby construct a mapping from process matrices with measurements to PDMs. The existence of this mapping implies that PDMs can, like the process matrix, model processes with indefinite causal orders. The results contribute to the unification of quantum models of spatiotemporal states.

pseudo-density matrix multiple-time states spacetime states indefinite causality process matrix

SCI

英语

第一 ; 通讯

National Research Foundation Singaporehttp://dx.doi.org/10.13039/501100001381["12050410246","1200509","12050410245"] ; National Natural Science Foundation of China[9610 623] ; National Research Foundation[MOE2012-T3-1-009]

Physics

Physics, Multidisciplinary

WOS:001184114100001

IOP Publishing Ltd

PHYSICS

Web of Science

1.Southern Univ Sci & Technol, Dept Phys, Shenzhen 518055, Peoples R China
2.City Univ Hong Kong, Dept Phys, Kowloon, Hong Kong, Peoples R China
3.Natl Univ Singapore, Ctr Quantum Technol, Singapore 117543, Singapore
4.Natl Univ Singapore, Dept Phys, Singapore 117543, Singapore
5.Southern Univ Sci & Technol, Shenzhen Inst Quantum Sci & Engn, Shenzhen 518055, Peoples R China
6.Southern Univ Sci & Technol, Inst Nanosci & Applicat, Shenzhen 518055, Peoples R China

Liu, Xiangjing,Jia, Zhian,Qiu, Yixian,et al. Unification of spatiotemporal quantum formalisms: mapping between process and pseudo-density matrices via multiple-time states[J]. NEW JOURNAL OF PHYSICS,2024,26(3).

Liu, Xiangjing,Jia, Zhian,Qiu, Yixian,Li, Fei,&Dahlsten, Oscar.(2024).Unification of spatiotemporal quantum formalisms: mapping between process and pseudo-density matrices via multiple-time states.NEW JOURNAL OF PHYSICS,26(3).

Liu, Xiangjing,et al."Unification of spatiotemporal quantum formalisms: mapping between process and pseudo-density matrices via multiple-time states".NEW JOURNAL OF PHYSICS 26.3(2024).