Quantum correlations with no causal order

Abstract

The idea that events obey a definite causal order is deeply rooted in our understanding of the world and at the basis of the very notion of time. But where does causal order come from, and is it a necessary property of nature? We address these questions from the standpoint of quantum mechanics in a new framework for multipartite correlations which does not assume a pre-defined global causal structure but only the validity of quantum mechanics locally. All known situations that respect causal order, including space-like and time-like separated experiments, are captured by this framework in a unified way. Surprisingly, we find correlations that cannot be understood in terms of definite causal order. These correlations violate a 'causal inequality' that is satisfied by all space-like and time-like correlations. We further show that in a classical limit causal order always arises, which suggests that space-time may emerge from a more fundamental structure in a quantum-to-classical transition.

13 pages, 5 figures

References in corpus (7)

• Informational derivation of Quantum Theory
• Characterizing quantum theory in terms of information-theoretic constraints
• A derivation of quantum theory from physical requirements
• Closed timelike curves via post-selection: theory and experimental demonstration
• Can closed timelike curves or nonlinear quantum mechanics improve quantum state discrimination or help solve hard problems?
• Perfect state distinguishability and computational speedups with postselected closed timelike curves
• Space-time and special relativity from causal networks

Cited by in corpus (431)

• Leggett-Garg Inequalities
• Non-Markovian quantum processes: complete framework and efficient characterisation
• Experimental Superposition of Orders of Quantum Gates
• Computational advantage from quantum-controlled ordering of gates
• Quantum mechanics and the covariance of physical laws in quantum reference frames
• Towards a Formulation of Quantum Theory as a Causally Neutral Theory of Bayesian Inference
• Experimental Verification of an Indefinite Causal Order
• Quantum causal modelling
• Enhanced communication with the assistance of indefinite causal order
• Perfect discrimination of no-signalling channels via quantum superposition of causal structures
• Indefinite Causal Order in a Quantum Switch
• Exponential Communication Complexity Advantage from Quantum Superposition of the Direction of Communication
• Quantum common causes and quantum causal models
• Witnessing causal nonseparability
• Quantum stochastic processes and quantum non-Markovian phenomena
• Quantum Metrology with Indefinite Causal Order
• Inferring causal structure: a quantum advantage
• Causal and causally separable processes
• Temporal quantum correlations and Leggett-Garg inequalities in multi-level systems
• A change of perspective: switching quantum reference frames via a perspective-neutral framework
• Experimental transmission of quantum information using a superposition of causal orders
• Experimental Quantum Switching for Exponentially Superior Quantum Communication Complexity
• Quantum superposition of the order of parties as a communication resource
• Bell's Theorem for Temporal Order
• Quantum circuits cannot control unknown operations
• Indefinite causal order enables perfect quantum communication with zero capacity channels
• Entanglement Between Photons that have Never Coexisted
• Quantum clocks and the temporal localisability of events in the presence of gravitating quantum systems
• The simplest causal inequalities and their violation
• Quantum Switch for the Quantum Internet: Noiseless Communications through Noisy Channels
• A resource theory of quantum memories and their faithful verification with minimal assumptions
• Quantum Blockchain using entanglement in time
• Experimental Quantum Communication Enhancement by Superposing Trajectories
• On Formalisms and Interpretations
• Beyond Bell's Theorem II: Scenarios with arbitrary causal structure
• Communication through coherent control of quantum channels
• Reversing Unknown Quantum Transformations: Universal Quantum Circuit for Inverting General Unitary Operations
• Computational advantage from quantum superposition of multiple temporal orders of photonic gates
• A temporal steering inequality
• Experimental non-locality in a quantum network
• Quantifying Bell: the Resource Theory of Nonclassicality of Common-Cause Boxes
• Communication through quantum-controlled noise
• Time-delocalized quantum subsystems and operations: on the existence of processes with indefinite causal structure in quantum mechanics
• Strict hierarchy between parallel, sequential, and indefinite-causal-order strategies for channel discrimination
• Maximal incompatibility of locally classical behavior and global causal order in multi-party scenarios
• Entanglement of quantum clocks through gravity
• Kolmogorov extension theorem for (quantum) causal modelling and general probabilistic theories
• Resource theories of communication
• Semidefinite programming strong converse bounds for classical capacity
• Quantum Markov Order
• The Structure of Quantum Stochastic Processes with Finite Markov Order
• A purification postulate for quantum mechanics with indefinite causal order
• Quantum circuits with classical versus quantum control of causal order
• Multipartite Causal Correlations: Polytopes and Inequalities
• A graph-separation theorem for quantum causal models
• Optimal quantum networks and one-shot entropies
• The space of logically consistent classical processes without causal order
• Cyclic Quantum Causal Models
• No-Signalling Assisted Zero-Error Capacity of Quantum Channels and an Information Theoretic Interpretation of the Lovasz Number
• Superdensity Operators for Spacetime Quantum Mechanics
• Theoretical framework for Higher-Order Quantum Theory
• Switching quantum reference frames in the N-body problem and the absence of global relational perspectives
• Machine Learning meets Quantum Foundations: A Brief Survey
• Can a quantum state over time resemble a quantum state at a single time?
• Temporal steering and security of quantum key distribution with mutually-unbiased bases against individual attacks
• Experimentally feasible computational advantage from quantum superposition of gate orders
• Noisy quantum metrology with the assistance of indefinite causal order
• Entanglement of a bipartite channel
• Fundamental limitations on distillation of quantum channel resources
• Functional Quantum Computing: An Optical Approach
• Optimal Strategies of Quantum Metrology with a Strict Hierarchy
• No Return to Classical Reality
• Channel capacity enhancement with indefinite causal order
• Work extraction from coherently activated maps via quantum switch
• Quantum Temporal Superposition: the case of QFT
• Updating the Born rule
• Experimental test of non-macrorealistic cat-states in the cloud
• Probabilistic exact universal quantum circuits for transforming unitary operations
• Quantum computation with indefinite causal structures
• Unruh-deWitt detectors in quantum superpositions of trajectories
• Two-way communication with a single quantum particle
• Operational quantum theory without predefined time
• Quantum and Classical Data Transmission through Completely Depolarising Channels in a Superposition of Cyclic Orders
• Thermodynamic advancement in the causally inseparable occurrence of thermal maps
• Operational formulation of time reversal in quantum theory
• No second law of entanglement manipulation after all
• Quantum-coherent mixtures of causal relations
• Quantum Theory, namely the pure and reversible theory of information
• Quantum theory as the most robust description of reproducible experiments
• Genuine quantum networks: superposed tasks and addressing
• Experiments on quantum causality
• Causal orders, quantum circuits and spacetime: distinguishing between definite and superposed causal orders
• Witnesses of causal nonseparability: an introduction and a few case studies
• On the definition and characterisation of multipartite causal (non)separability
• Witnessing quantum memory in non-Markovian processes
• Experimental entanglement of temporal order
• Quantum speedup in the identification of cause-effect relations
• Entanglement, non-Markovianity, and causal non-separability
• Experimental Aspects of Indefinite Causal Order in Quantum Mechanics
• Quantum operations with indefinite time direction
• Tensor network simulation of chains of non-Markovian open quantum systems
• Why initial system-environment correlations do not imply the failure of complete positivity: a causal perspective
• Dynamics of quantum causal structures
• Causal structures and the classification of higher order quantum computations
• How device-independent approaches change the meaning of physical theory
• A channel-based framework for steering, non-locality and beyond
• Experimental characterisation of a non-Markovian quantum process
• Connecting processes with indefinite causal order and multi-time quantum states
• Unitary channel discrimination beyond group structures: Advantages of sequential and indefinite-causal-order strategies
• Reconstructing quantum theory from diagrammatic postulates
• Thermal devices powered by generalized measurements with indefinite causal order
• Hierarchy in temporal quantum correlations
• Quantum superposition of thermodynamic evolutions with opposing time's arrows
• Quantum non-Markovianity: Overview and recent developments
• Classical Communications with Indefinite Causal Order for $N$ completely depolarizing channels
• Causal Boxes: Quantum Information-Processing Systems Closed under Composition
• Bounding quantum correlations with indefinite causal order
• A Unifying Framework for Spatial and Temporal Quantum Correlations
• Superposition of causal order enables perfect quantum teleportation with very noisy singlets
• Causality re-established
• Causal limit on quantum communication
• Resource theories of multi-time processes: A window into quantum non-Markovianity
• Monotone Measures for Non-Local Correlations
• Bridging the gap between general probabilistic theories and the device-independent framework for nonlocality and contextuality
• Quantification of quantum dynamics with input-output games
• Genuine Multipartite Entanglement in Time
• Causally nonseparable processes admitting a causal model
• Causation does not explain contextuality
• A quantum causal discovery algorithm
• Deterministic transformations between unitary operations: Exponential advantage with adaptive quantum circuits and the power of indefinite causality
• Thermodynamics of quantum switch information capacity activation
• Random-Receiver Quantum Communication
• Perfect signaling among three parties violating predefined causal order
• Causal order as a resource for quantum communication
• Observer-dependent locality of quantum events
• OQuPy: A Python package to efficiently simulate non-Markovian open quantum systems with process tensors
• Quantum parameter estimation on coherently superposed noisy channels
• Leggett-Garg Macrorealism and temporal correlations
• Quantum Correlations and Quantum Non-locality: a review and a few new ideas
• Indefinite causal order for quantum metrology with quantum thermal noise
• Causal structure in the presence of sectorial constraints, with application to the quantum switch
• Analysing causal structures with entropy
• Semi-device-independent certification of indefinite causal order
• Noncausal Page-Wootters circuits
• Thermodynamics of Quantum Causal Models: An Inclusive, Hamiltonian Approach
• Experimental Demonstration of Instrument-specific Quantum Memory Effects and Non-Markovian Process Recovery for Common-Cause Processes
• Indefinite causal structures for continuous-variable systems
• Any consistent coupling between classical gravity and quantum matter is fundamentally irreversible
• Quantum teleportation with relativistic communication from first principles
• Markovianization with approximate unitary designs
• Symmetries of quantum evolutions
• Theoretical description and experimental simulation of quantum entanglement near open time-like curves via pseudo-density operators
• A fundamental problem in quantizing general relativity
• Resource theory of causal connection
• Device-independent test of causal order and relations to fixed-points
• Semi-device-independent certification of indefinite causal order in a photonic quantum switch
• Information-theoretic constraints on correlations with indefinite causal order
• The entropic approach to causal correlations
• Simple and maximally robust processes with no classical common-cause or direct-cause explanation
• Non-Markovian Memory Strength Bounds Quantum Process Recoverability
• Quantum clocks and their synchronisation - the Alternate Ticks Game
• Exploring quantum thermodynamics with NMR
• Thermality, causality and the quantum-controlled Unruh-deWitt detector
• Success-or-Draw: A Strategy Allowing Repeat-Until-Success in Quantum Computation
• Higher-order Process Matrix Tomography of a passively-stable Quantum SWITCH
• Identification is Pointless: Quantum Coordinates, Localisation of Events, and the Quantum Hole Argument
• Acausal measurement-based quantum computing
• Reversible time travel with freedom of choice
• Evading noise in multiparameter quantum metrology with indefinite causal order
• Consequences of preserving reversibility in quantum superchannels
• Composable security in relativistic quantum cryptography
• Quantum superpositions of "common-cause" and "direct-cause" causal structures
• Relaxation of Multitime Statistics in Quantum Systems
• Routed quantum circuits
• Reversible dynamics with closed time-like curves and freedom of choice
• Quantum theory as plausible reasoning applied to data obtained by robust experiments
• Demonstration of a quantum SWITCH in a Sagnac configuration
• Unlimited non-causal correlations and their relation to non-locality
• Generating multi-partite entanglement from the quantum vacuum with a finite-lifetime mirror
• Computational tameness of classical non-causal models
• Characterising the Hierarchy of Multi-time Quantum Processes with Classical Memory
• A general framework for cyclic and fine-tuned causal models and their compatibility with space-time
• Deterministic Generation of Multipartite Entanglement via Causal Activation in the Quantum Internet
• Causal and compositional structure of unitary transformations
• Timelessness strictly inside the Quantum Realm
• Optimal processing of reversible quantum channels
• Entanglement Entropy of Free Fermions in Timelike Slices
• Reassessing thermodynamic advantage from indefinite causal order
• Quantum causal correlations and non-Markovianity of quantum evolution
• Fully-Optimized Quantum Metrology: Framework, Tools, and Applications
• Reassessing the advantage of indefinite causal orders for quantum metrology
• Process Products Need Qualification
• Experimental superposition of time directions
• Inferring the arrow of time in quantum spatiotemporal correlations
• Quantum Causal Influence
• Causal classification of spatiotemporal quantum correlations
• Space-time dual quantum Zeno effect: Interferometric engineering of open quantum system dynamics
• Uniqueness of quantum state over time function
• Quantum Information in Relativity: the Challenge of QFT Measurements
• Genuinely Multipartite Noncausality
• Quantum Causal Models
• Quantum superpositions of causal orders as an operational resource
• Indefinite Causal Orders from Superpositions in Time
• Signatures of quantum chaos in an out-of-time-order tensor
• Equilibration of Multitime Quantum Processes in Finite Time Intervals
• Quantum steering beyond instrumental causal networks
• Experimental demonstration of input-output indefiniteness in a single quantum device
• Reassessing the computational advantage of quantum-controlled ordering of gates
• Simulating indefinite causal order with Rindler observers
• Quantum space-time marginal problem: global causal structure from local causal information
• Multipartite Nonlocality as a Resource and Quantum Correlations Having Indefinite Causal Order
• Necessary and Sufficient Conditions on Measurements of Quantum Channels
• Unification of spatiotemporal quantum formalisms: mapping between process and pseudo-density matrices via multiple-time states
• Quantum communication through devices with indefinite input-output direction
• Existence of processes violating causal inequalities on time-delocalised subsystems
• Comparing the quantum switch and its simulations with energetically-constrained operations
• Impossibility of superluminal signalling in Minkowski space-time does not rule out causal loops
• Memory Effects in Quantum Processes
• Acausal quantum theory for non-Archimedean scalar fields
• Anomalous Weak Values Without Post-Selection
• Different instances of time as different quantum modes: quantum states across space-time for continuous variables
• Postselected quantum hypothesis testing
• Embedding cyclic information-theoretic structures in acyclic spacetimes: no-go results for indefinite causality
• Dynamical nonlocality in quantum time via modular operators
• Non-causal computation
• Correlation Measure Equivalence in Dynamic Causal Structures of Quantum Gravity
• Experimentally demonstrating indefinite causal order algorithms to solve the generalized Deutsch's problem
• Activating information backflow with the assistance of quantum SWITCH
• Semi-Device-Independent Certification of Causal Nonseparability with Trusted Quantum Inputs
• Causal games of work extraction with indefinite causal order
• Fundamental limits for realising quantum processes in spacetime
• Causality - Complexity - Consistency: Can Space-Time Be Based on Logic and Computation?
• Quantum Causal Inference with Extremely Light Touch
• Improvement in quantum communication using quantum switch
• Breaking the limits of purification: Postselection enhances heat-bath algorithmic cooling
• Separation between quantum Lovász number and entanglement-assisted zero-error classical capacity
• Quantum switch instabilities with an open control
• Two-qubit causal structures and the geometry of positive qubit-maps
• Optimal universal quantum circuits for unitary complex conjugation
• Quantum switch in the gravity of Earth
• Quantum communication using a quantum switch of quantum switches
• Classical communication through quantum causal structures
• Can quantum non-locality be connected to extra-dimensions?
• Theory of Quantum Gravity Information Processing
• Quantum enhancement to information acquisition speed
• Higher-order quantum transformations of Hamiltonian dynamics
• Quantum networks boosted by entanglement with a control system
• Monitored non-adiabatic and coherent-controlled quantum unital Otto heat engines: First four cumulants
• Composition rules for quantum processes: a no-go theorem
• From Non-Markovian Dissipation to Spatiotemporal Control of Quantum Nanodevices
• Universal construction of decoders from encoding black boxes
• Memory in quantum processes with indefinite time direction and causal order
• Popescu-Rohrlich box implementation in general probabilistic theory of processes
• Dimension-independent weak value estimation via controlled SWAP operations
• Experimentally adjudicating between different causal accounts of Bell inequality violations via statistical model selection
• Equivalence Principle in Classical and Quantum Gravity
• Gravitational quantum switch on a superposition of spherical shells
• Probabilistic Theories and Reconstructions of Quantum Theory (Les Houches 2019 lecture notes)
• Entanglement-assisted classical communication can simulate classical communication without causal order
• Quantum superposition of causal structures as a universal resource for local implementation of nonlocal quantum operations
• Practical computational advantage from the quantum switch on a generalized family of promise problems
• Separation of conditions as a prerequisite for quantum theory
• Measurement events relative to temporal quantum reference frames
• Indefinite causal order and quantum coordinates
• Using Quantum Switches to Mitigate Noise in Grover's Search Algorithm
• Characterizing quantum instruments: from non-demolition measurements to quantum error correction
• The Sheaf-Theoretic Structure of Definite Causality
• A no-go theorem for superpositions of causal orders
• Quantum chicken-egg dilemmas: Delayed-choice causal order and the reality of causal non-separability
• Admissible Causal Structures and Correlations
• Equivalence of Grandfather and Information Antinomy Under Intervention
• Interference as an information-theoretic game
• The spatiotemporal doubled density operator: a unified framework for analyzing spatial and temporal quantum processes
• Quantum and classical effects in a light-clock falling in Schwarzschild geometry
• Quantifying Superpositions Between Quantum Evolutions
• Quantum from principles without assuming definite causal structure
• Role of quantum correlations in daemonic expected utility
• Quantum to classical transitions in causal relations
• Picturing Indefinite Causal Structure
• Appearance of causality in process matrices when performing fixed-basis measurements for two parties
• Spinning up a Time Machine
• No nonlocal advantage of quantum coherence beyond quantum instrumentality
• Strategies for single-shot discrimination of process matrices
• A Diagrammatic Approach to Information Transmission in Generalised Switches
• Quantum dynamics as a pseudo-density matrix
• Quantum and classical dynamical semigroups of superchannels and semicausal channels
• Channel discrimination power of bipartite quantum states
• The quantum switch is uniquely defined by its action on unitary operations
• Building Multiple Access Channels with a Single Particle
• No-signalling constrains quantum computation with indefinite causal structure
• Quantum Supermaps are Characterized by Locality
• Causal influence in operational probabilistic theories
• Exploring the limits of no backward in time signalling
• A Combinatorial Solution to Causal Compatibility
• Generalizing Entanglement
• Multipartite quantum states over time from two fundamental assumptions
• Trading causal order for locality
• Network-Device-Independent Certification of Causal Nonseparability
• Taxonomy for Physics Beyond Quantum Mechanics
• Relating Wigner's Friend Scenarios to Nonclassical Causal Compatibility, Monogamy Relations, and Fine Tuning
• Classical and Quantum Causal Interventions
• Addressable quantum gates
• Computable lower bounds on the entanglement cost of quantum channels
• Experimental implementation of arbitrary entangled operations
• Relativity of quantum states in entanglement swapping: Violation of Bell's inequality with no entanglement
• The Operational Choi-Jamiolkowski Isomorphism
• On characterising assemblages in Einstein-Podolsky-Rosen scenarios
• Interplay between the Hilbert-space dimension of a control system and the memory induced by a quantum SWITCH
• Indefinite causal order for quantum phase estimation with Pauli noise
• On the quantum no-signalling assisted zero-error classical simulation cost of non-commutative bipartite graphs
• The Multi-round Process Matrix
• Indefinite causal key distribution
• Variations on the Choi-Jamiolkowski isomorphism
• A Spacetime Area Law Bound on Quantum Correlations
• Revisiting dynamics of quantum causal structures -- when can causal order evolve?
• Semi-device-independent certification of quantum non-Markovianity using sequential Random Access Codes
• How Deep the Theory of Quantum Communications Goes: Superadditivity, Superactivation and Causal Activation
• Quantum Query Complexity of Boolean Functions under Indefinite Causal Order
• A no-go theorem for theories that decohere to quantum mechanics
• Coherent control of the causal order of entanglement distillation
• Indefinite Time Directed Quantum Metrology
• Combining contextuality and causality: a game semantics approach
• Bell Correlations and the Common Future
• Tsirelson bounds for quantum correlations with indefinite causal order
• Quantifying Quantum Causal Influences
• The Möbius game and other Bell tests for relativity
• Operational interpretation of the vacuum and process matrices for identical particles
• Universal adjointation of isometry operations using conversion of quantum supermaps
• Causality Violation and Nonlinear Quantum Mechanics
• Mapping indefinite causal order processes to composable quantum protocols in a spacetime
• Quantifying Causal Influence in Quantum Mechanics
• A computational test of quantum contextuality, and even simpler proofs of quantumness
• Time Symmetry in Operational Theories
• Smooth Entropy Transfer of Quantum Gravity Information Processing
• Hamiltonian characterisation of multi-time processes with classical memory
• Toward an Experimental Device-Independent Verification of Indefinite Causal Order
• Topological obstructions to quantum computation with unitary oracles
• Consistent circuits for indefinite causal order
• Quantum process discrimination with restricted strategies
• Quantifying information flow in quantum processes
• Emergent non-Markovianity and dynamical quantification of the quantum switch
• The operational framework for quantum theories is both epistemologically and ontologically neutral
• The Min-Entropy of Classical-Quantum Combs for Measurement-Based Applications
• Entropic witness for quantum memory in open system dynamics
• Decoherence to quantum theory from a causally-indefinite post-quantum theory
• Witnessing environment dimension through temporal correlations
• Reality, Causality, and Quantum Theory
• Evaluating probabilistic programming languages for simulating quantum correlations
• Complete extension: the non-signaling analog of quantum purification
• Multi-time quantum process tomography on a superconducting qubit
• Error-free interconversion of nonlocal boxes
• On quantum superpositions of graphs, no-signalling and covariance
• Recovery of damaged information via scrambling in indefinite casual order
• Quantum theory cannot violate a causal inequality
• Quantum networks theory
• Parameterized quantum comb and simpler circuits for reversing unknown qubit-unitary operations
• Simulating the quantum switch with quantum circuits is computationally hard
• Simulating violation of causality using a topological phase transition
• Empirical adequacy of the time operator canonically conjugate to a Hamiltonian generating translations
• Expressibility, entangling power and quantum average causal effect for causally indefinite circuits
• Relativistic Causality vs. No-Signaling as the limiting paradigm for correlations in physical theories
• Path superposition activating perfect quantum teleportation ability for separable states
• Implications of Local Friendliness violation for quantum causality
• Conditional mutual information: A generalization of causal inference in quantum systems
• Background Independence and Quantum Causal Structure
• Non-commutativity as a Universal Characterization for Enhanced Quantum Metrology
• Biased Non-Causal Game
• Weak Particle Presence
• Quantum switch as a thermodynamic resource in the context of passive states
• Entanglement, Complexity, and Causal Asymmetry in Quantum Theories
• Hierarchy and robustness of multilevel two-time temporal quantum correlations
• Causality in Higher Order Process Theories
• Quantum Correlations in Space-Time: Foundations and Applications
• Counting Risk Increments to Make Decisions During an Epidemic
• Correlational quantum theory and correlation constraints
• Causal nonseparability and its implications for spatiotemporal relations
• Enhancement of non-Stabilizerness within Indefinite Causal Order
• Breaking absolute separability with quantum switch
• Remote Creation of Quantum Coherence via Indefinite Causal Order
• Activated zero-error classical communication over quantum channels assisted with quantum no-signalling correlations
• Demolishing prejudices to get to the foundations: a criterion of demarcation for fundamentality
• Equilibration and Typicality in Quantum Processes
• Quantum Advantage in Storage and Retrieval of Isometry Channels
• Algebraic and geometric properties of local transformations
• World quantum gravity: Quantum test objects and Synge's world function
• Conditional probability and interferences in generalized measurements with or without definite causal order
• Giving Operational Meaning to the Superposition of Causal Orders
• Sequential device-independent certification of indefinite causal order
• Doubly Quantum Mechanics
• Tsirelson's Bound and the Quantum Monogamy Bound from Global Determinism
• Signatures of causality and determinism in a quantum theory of events
• Classical communication cost of a bipartite quantum channel assisted by non-signalling correlations
• Optimal quantum precision in noise estimation: Is entanglement necessary?
• Comment on "Revisiting dynamics of quantum causal structures --when can causal order evolve?''
• Characterising transformations between quantum objects, 'completeness' of quantum properties, and transformations without a fixed causal order
• On the One-Shot Zero-Error Classical Capacity of Classical-Quantum Channels Assisted by Quantum Non-signalling Correlations
• A de Finetti theorem for quantum causal structures
• Tripartite non-classical correlations without backwards in time signalling
• Bounds on Multipartite Nonlocality via Reduction to Biased Nonlocality
• Quantum probabilities for the causal ordering of events
• Knot invariants and indefinite causal order
• No quantum advantage for violating fixed-order inequalities?
• Optimal Hamiltonian recognition of unknown quantum dynamics
• Causal influence versus signalling for interacting quantum channels
• Ideal stochastic process modeling with post-quantum quasiprobabilistic theories
• Efficient and operational quantifier of non-divisibility in terms of channel discrimination
• Causality in a qubit-based quantum switch
• IMALL with a Mixed-State Modality: A Logical Approach to Quantum Computation
• Process Tensor Approaches to Non-Markovian Quantum Dynamics
• Summoning, No-Signaling and Relativistic Bit Commitments
• Ordering the processes with indefinite causal order
• Correlations in a quantum switch-based heat engine with measurements: A proof-of-principle demonstration
• Quantum Entanglement in Time
• A Profunctorial Semantics for Quantum Supermaps
• Telefilters, telemirrors, and causality
• Forward-backward stochastic simulations: Q-based model for measurement and Bell-nonlocality consistent with weak local realistic premises
• Blind-spots of Randomized Benchmarking Under Temporal Correlations
• Entropic uncertainty under indefinite causal order and input-output direction
• The standard no-signalling constraints in Bell scenarios are neither sufficient nor necessary for preventing superluminal signalling with general interventions
• Subsystems (in)dependence in GIE proposals
• Robust device-independent characterization of sharpness and incompatibility of unsharp instruments
• Fast tests for probing the causal structure of quantum processes
• Classical and Quantum Query Complexity of Boolean Functions under Indefinite Causal Order
• An axiomatic measure of one-way quantum information
• Relativistic Particle Motion and Quantum Optics in a Weak Gravitational Field
• Information Exchange in Causally Nonseparable Processes
• Preprocessing operations and the reverse compression
• Indefinite global time
• An All-Or-Nothing Flavor to the Church-Turing Hypothesis
• Quantum causal models via QBism
• Flow of dynamical causal structures with an application to correlations