8 papers · 1 filter
Quantum Mutual Information in Time
James Fullwood, Zhen Wu, Arthur J. Parzygnat +1
While the quantum mutual information is a fundamental measure of quantum information, it is only defined for spacelike-separated quantum systems. Such a limitation is not present i…
Multipartite quantum states over time from two fundamental assumptions
Seok Hyung Lie, James Fullwood
The theory of quantum states over time extends the density operator formalism into the temporal domain, providing a unified of treatment of timelike and spacelike separated systems…
Time-symmetric correlations for open quantum systems
Arthur J. Parzygnat, James Fullwood
Two-time expectation values of sequential measurements of dichotomic observables are known to be time symmetric for closed quantum systems. Namely, if a system evolves unitarily be…
General Communication Enhancement via the Quantum Switch
Zhen Wu, James Fullwood, Zhihao Ma +3
Recent studies have shown that quantum information may be effectively transmitted by a finite collection of completely depolarizing channels in a coherent superposition of differen…
Operator representation of spatiotemporal quantum correlations
James Fullwood, Arthur J. Parzygnat
While quantum correlations between two spacelike-separated systems are fully encoded by the bipartite density operator associated with the joint system, there does not exist an ana…
General covariance for quantum states over time
James Fullwood
The theory of quantum states over time provides an approach to the dynamics of quantum information which is in direct analogy with spacetime and its relation to classical dynamics.…