Process Products Need Qualification
arXiv:1706.05532 · doi:10.1103/PhysRevA.97.032110
Abstract
The quantum process framework is devised as a generalization of quantum theory to incorporate indefinite causal structure. In this short paper we point out a restriction in forming products of processes: there exist both classical and quantum processes whose tensor products are not processes. Our main result is a necessary and sufficient condition for when tensor products of multipartite processes are (in)valid. We briefly discuss the implications of this restriction on process communication theory.
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References in corpus (13)
- Quantum correlations with no causal order
- Quantum computations without definite causal structure
- Theoretical framework for quantum networks
- Computational advantage from quantum-controlled ordering of gates
- Towards a Formulation of Quantum Theory as a Causally Neutral Theory of Bayesian Inference
- Towards Quantum Gravity: A Framework for Probabilistic Theories with Non-Fixed Causal Structure
- Exponential Communication Complexity Advantage from Quantum Superposition of the Direction of Communication
- Witnessing causal nonseparability
- Causal and causally separable processes
- Quantum superposition of the order of parties as a communication resource
- "No Information Without Disturbance": Quantum Limitations of Measurement
- Operational quantum theory without predefined time
- Device-independent test of causal order and relations to fixed-points
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- Composition rules for quantum processes: a no-go theorem
- Quantum from principles without assuming definite causal structure
- Revisiting dynamics of quantum causal structures -- when can causal order evolve?
- Mapping indefinite causal order processes to composable quantum protocols in a spacetime
- Comparative analysis of robust entanglement generation in engineered XX spin chains