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Published on: May 30, 2014
Multipartite Quantum States over Time from Two Fundamental Assumptions
Seok Hyung Lie1, James Fullwood2
1Ulsan National Institute of Science and Technology (UNIST), Department of Physics, Ulsan 44919, Republic of Korea.
This study extends quantum states over time to multipartite systems, uniquely defining their Markovian extension. This work enables experimental verification of temporal correlations using quantum snapshotting.
Area of Science:
- Quantum Information Theory
- Quantum Foundations
- Temporal Quantum Mechanics
Background:
- Quantum states over time extend density operators to the temporal domain, unifying timelike and spacelike separated systems.
- Current understanding is limited to bipartite systems, with multipartite temporal scenarios like Leggett-Garg inequalities remaining unclear.
Purpose of the Study:
- To consistently extend the concept of quantum states over time to multipartite systems.
- To identify the unique Markovian extension for multipartite quantum states over time.
Main Methods:
- Applying two key assumptions: linearity in the initial state and a quantum analog of conditionability.
- Establishing a correspondence between multipartite quantum states over time and Kirkwood-Dirac quasiprobability distributions.
Main Results:
- The unique Markovian extension of bipartite quantum states over time to multipartite systems is identified.
- A direct link is established between multipartite quantum states over time and Kirkwood-Dirac quasiprobability distributions.
Conclusions:
- The findings provide a consistent framework for multipartite quantum states over time.
- The established correspondence facilitates experimental verification of temporal correlations via quantum snapshotting.
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