# Device-independent certification of indefinite causal order in the quantum switch

@inproceedings{Lugt2022DeviceindependentCO, title={Device-independent certification of indefinite causal order in the quantum switch}, author={Tein van der Lugt and Jonathan Barrett and Giulio Chiribella}, year={2022} }

Quantum theory is compatible with scenarios in which the order of operations is indeﬁnite. Experimental investigations of such scenarios, all of which have been based on a process known as the quantum switch, have provided demonstrations of indeﬁnite causal order conditioned on assumptions on the devices used in the laboratory. But is a device-independent certiﬁcation possible, similar to the certiﬁcation of entanglement through Bell inequalities? Despite previous evidence suggesting a negative…

## 3 Citations

### Quantum Supermaps are Characterized by Locality

- Computer Science
- 2022

We prove that the sequential and parallel composition rules for quantum channels are all that need to be referenced to axiomatise quantum supermaps from ﬁrst principles. To do so we provide a simple…

### Existence of processes violating causal inequalities on time-delocalised subsystems

- Philosophy, MathematicsNature Communications
- 2023

It has been shown that it is theoretically possible for there to exist quantum and classical processes in which the operations performed by separate parties do not occur in a well-defined causal…

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