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Related papers: Picturing Indefinite Causal Structure

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When transforming pairs of independent quantum operations according to the fundamental rules of quantum theory, an intriguing phenomenon emerges: some such higher-order operations may act on the input operations in an indefinite causal…

Quantum Physics · Physics 2022-02-08 Jessica Bavaresco , Mateus Araújo , Časlav Brukner , Marco Túlio Quintino

Unlike the relativity theory it seeks to replace, causal set theory has been interpreted to leave space for a substantive, though perhaps 'localized', form of 'becoming'. The possibility of fundamental becoming is nourished by the fact that…

History and Philosophy of Physics · Physics 2015-02-03 Christian Wuthrich , Craig Callender

Recent frameworks describing quantum mechanics in the absence of a global causal order admit the existence of causally indefinite processes, where it is impossible to ascribe causal order for events A and B. These frameworks even allow for…

Quantum Physics · Physics 2021-05-11 Simon Milz , Dominic Jurkschat , Felix A. Pollock , Kavan Modi

Formalisms for higher order quantum processes provide a theoretical formalisation of quantum processes where the order of agents' operations need not be definite and acyclic, but may be subject to quantum superpositions. This has led to the…

Quantum Physics · Physics 2025-08-07 Matthias Salzger , V. Vilasini

Quantum theory allows for the superposition of causal orders between operations, i.e., for an indefinite causal order; an implication of the principle of quantum superposition. Since a higher theory might also admit this feature, an…

Quantum Physics · Physics 2024-11-08 Kuntal Sengupta

There is growing interest in the study of causal methods in the Earth sciences. However, most applications have focused on causal discovery, i.e. inferring the causal relationships and causal structure from data. This paper instead examines…

Atmospheric and Oceanic Physics · Physics 2021-05-04 Adam Massmann , Pierre Gentine , Jakob Runge

Over the past decade, a number of quantum processes have been proposed which are logically consistent, yet feature a cyclic causal structure. However, there is no general formal method to construct a process with an exotic causal structure…

Quantum Physics · Physics 2025-12-03 Augustin Vanrietvelde , Nick Ormrod , Hlér Kristjánsson , Jonathan Barrett

Causal nonseparability refers to processes where events take place in a coherent superposition of different causal orders. These may be the key resource for experimental violations of causal inequalities and have been recently identified as…

Quantum Physics · Physics 2019-12-16 Márcio M. Taddei , Ranieri V. Nery , Leandro Aolita

In the last few years, there has been increasing interest in quantum processes with indefinite causal order. Process matrices are a convenient framework to study such processes. Ref. [1] defines higher order transformations from process…

Quantum Physics · Physics 2020-09-22 Esteban Castro-Ruiz , Flaminia Giacomini , Časlav Brukner

Using a process-theoretic formalism, we introduce the notion of a causal-inferential theory: a triple consisting of a theory of causal influences, a theory of inferences (of both the Boolean and Bayesian varieties), and a specification of…

Quantum Physics · Physics 2021-05-21 David Schmid , John H. Selby , Robert W. Spekkens

Neurally-parameterized Structural Causal Models in the Pearlian notion to causality, referred to as NCM, were recently introduced as a step towards next-generation learning systems. However, said NCM are only concerned with the learning…

Machine Learning · Computer Science 2022-12-27 Matej Zečević , Devendra Singh Dhami , Kristian Kersting

In this article we set out to understand the significance of the process matrix formalism and the quantum causal modelling programme for ongoing disputes about the role of causation in fundamental physics. We argue that the process matrix…

Quantum Physics · Physics 2022-08-05 Emily Adlam

Discussions on causal relations in real life often consider variables for which the definition of causality is unclear since the notion of interventions on the respective variables is obscure. Asking 'what qualifies an action for being an…

Methodology · Statistics 2022-11-17 Dominik Janzing , Sergio Hernan Garrido Mejia

Interpretability research on large language models (LLMs) has yielded important insights into model behaviour, yet recurring pitfalls persist: findings that do not generalise, and causal interpretations that outrun the evidence. Our…

Machine Learning · Computer Science 2026-03-20 Shruti Joshi , Aaron Mueller , David Klindt , Wieland Brendel , Patrik Reizinger , Dhanya Sridhar

We develop an extension of the process matrix (PM) framework for correlations between quantum operations with no causal order that allows multiple rounds of information exchange for each party compatibly with the assumption of well-defined…

Quantum Physics · Physics 2021-01-27 Timothée Hoffreumon , Ognyan Oreshkov

We develop relativistic causality theory in the setting of point-free topology by introducing a notion of causal coverage in ordered locales, generalising their canonical coverage relation to incorporate causal structure. This improves…

Mathematical Physics · Physics 2025-10-21 Chris Heunen , Nesta van der Schaaf

Many fundamental and key objects in quantum mechanics are linear mappings between particular affine/linear spaces. This structure includes basic quantum elements such as states, measurements, channels, instruments, non-signalling channels…

Quantum Physics · Physics 2024-07-19 Simon Milz , Marco Túlio Quintino

We study causal inference in a multi-environment setting, in which the functional relations for producing the variables from their direct causes remain the same across environments, while the distribution of exogenous noises may vary. We…

Machine Learning · Computer Science 2017-05-29 AmirEmad Ghassami , Saber Salehkaleybar , Negar Kiyavash , Kun Zhang

We consider the reversible processes between two one-to-one correlated measurement outcomes which underly both problem-solving and quantum nonlocality. In the former case the two outcomes are the setting and the solution of the problem, in…

Quantum Physics · Physics 2021-09-08 Giuseppe Castagnoli

Causal inference is often portrayed as fundamentally distinct from predictive modeling, with its own terminology, goals, and intellectual challenges. But at its core, causal inference is simply a structured instance of prediction under…

Machine Learning · Computer Science 2025-07-10 Carlos Fernández-Loría