Perfect signaling among three parties violating predefined causal order

Abstract

The paradigmatic view where information is seen as a more fundamental concept than the laws of physics leads to a different understanding of spacetime where the causal order of events emerges from correlations between random variables representing physical quantities. In particular, such an information-theoretic approach does not enforce a global spacetime structure. By following this path, we conclude that perfect signaling correlations among three parties are possible which do not obey the restrictions imposed by global spacetime. We show this using a recent framework based on the sole assumptions that locally, quantum theory is valid and random variables can be described by probability distributions. Our result is of zero-error type and is an analog to a tripartite appearance of quantum non-locality which manifests itself by satisfying a condition with certainty whereas the same is impossible for any local theory.

5 pages, 3 figures, 2 tables, references added

References in corpus (3)

• Characterizing quantum theory in terms of information-theoretic constraints
• No extension of quantum theory can have improved predictive power
• Towards Quantum Gravity: A Framework for Probabilistic Theories with Non-Fixed Causal Structure

Cited by in corpus (25)

• Experimental Verification of an Indefinite Causal Order
• Witnessing causal nonseparability
• Time-delocalized quantum subsystems and operations: on the existence of processes with indefinite causal structure in quantum mechanics
• A purification postulate for quantum mechanics with indefinite causal order
• Cyclic Quantum Causal Models
• Theoretical framework for Higher-Order Quantum Theory
• Witnesses of causal nonseparability: an introduction and a few case studies
• On the definition and characterisation of multipartite causal (non)separability
• Experimental Aspects of Indefinite Causal Order in Quantum Mechanics
• Causal structures and the classification of higher order quantum computations
• How device-independent approaches change the meaning of physical theory
• Connecting processes with indefinite causal order and multi-time quantum states
• Causal Boxes: Quantum Information-Processing Systems Closed under Composition
• Analysing causal structures with entropy
• The entropic approach to causal correlations
• Unlimited non-causal correlations and their relation to non-locality
• Computational tameness of classical non-causal models
• Genuinely Multipartite Noncausality
• Causality - Complexity - Consistency: Can Space-Time Be Based on Logic and Computation?
• Equivalence of Grandfather and Information Antinomy Under Intervention
• The Sheaf-Theoretic Structure of Definite Causality
• Quantum Supermaps are Characterized by Locality
• Trading causal order for locality
• Relating Wigner's Friend Scenarios to Nonclassical Causal Compatibility, Monogamy Relations, and Fine Tuning
• Exploring the limits of no backward in time signalling