English
Related papers

Related papers: Quantum Causal Unravelling

200 papers

Causal knowledge is vital for effective reasoning in science, as causal relations, unlike correlations, allow one to reason about the outcomes of interventions. Algorithms that can discover causal relations from observational data are based…

Machine Learning · Statistics 2019-11-12 Anish Dhir , Ciarán M. Lee

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

The landscape of causal relations that can hold among a set of systems in quantum theory is richer than in classical physics. In particular, a pair of time-ordered systems can be related as cause and effect or as the effects of a common…

Quantum Physics · Physics 2017-07-20 Katja Ried , Jean-Philippe W. MacLean , Robert W. Spekkens , Kevin J. Resch

The ability to identify cause-effect relations is an essential component of the scientific method. The identification of causal relations is generally accomplished through statistical trials where alternative hypotheses are tested against…

Quantum Physics · Physics 2019-04-03 Giulio Chiribella , Daniel Ebler

The first application of a quantum algorithm to Feynman loop integrals is reviewed. The connection between quantum computing and perturbative quantum field theory is feasible due to fact that the two on-shell states of a Feynman propagator…

Quantum Physics · Physics 2022-11-11 Selomit Ramírez-Uribe

Quantum physics is a linear theory, so it is somewhat puzzling that it can underlie very complex systems such as digital computers and life. This paper investigates how this is possible. Physically, such complex systems are necessarily…

Quantum Physics · Physics 2024-03-12 George F R Ellis

Reconstructions of quantum theory usually implicitly assume that experimental events are ordered within a global causal structure. The process matrix framework accommodates quantum correlations that violate an inequality verified by all…

Quantum Physics · Physics 2015-11-24 Issam Ibnouhsein , Alexei Grinbaum

Ever since entanglement was identified as a computational and cryptographic resource, effort has been made to find an efficient way to tell whether a given density matrix represents an unentangled, or separable, state. Essentially, this is…

Data Structures and Algorithms · Computer Science 2007-05-23 Lawrence M. Ioannou

While the standard formulation of quantum theory assumes a fixed background causal structure, one can relax this assumption within the so-called process matrix framework. Remarkably, some processes, termed causally nonseparable, are…

Quantum Physics · Physics 2022-08-29 Hippolyte Dourdent , Alastair A. Abbott , Nicolas Brunner , Ivan Šupić , Cyril Branciard

We give a causal inference scheme using quantum observations alone for a case with both temporal and spatial correlations: a bipartite quantum system with measurements at two times. The protocol determines compatibility with 5 causal…

Quantum Physics · Physics 2025-04-01 Xiangjing Liu , Yixian Qiu , Oscar Dahlsten , Vlatko Vedral

Modern machine learning (ML) methods typically fail to adequately capture causal information. Consequently, such models do not handle data distributional shifts, are vulnerable to adversarial examples, and often learn spurious correlations.…

Quantum Physics · Physics 2026-01-27 Rishi Goel , Casey R. Myers , Sally Shrapnel

A central question for causal inference is to decide whether a set of correlations fit a given causal structure. In general, this decision problem is computationally infeasible and hence several approaches have emerged that look for…

Quantum Physics · Physics 2018-07-26 Mirjam Weilenmann , Roger Colbeck

While quantum computers promise significant advantages, the complexity of quantum algorithms remains a major technological obstacle. We have developed and demonstrated an architecture-independent technique that simplifies adding control…

Quantum computers use the quantum interference of different computational paths to enhance correct outcomes and suppress erroneous outcomes of computations. A common pattern underpinning quantum algorithms can be identified when quantum…

Quantum Physics · Physics 2009-10-30 Richard Cleve , Artur Ekert , Chiara Macchiavello , Michele Mosca

Quantum mechanics allows operations to be in indefinite causal order. Recently there have been active discussions on enhanced communication strategies through exotic causal structures. In light of this, through the process matrix formalism,…

Quantum Physics · Physics 2021-04-21 Kaumudibikash Goswami , Fabio Costa

This thesis reports progress in two domains, causal structures and microscopic thermodynamics, both of which are pertinent in the development of quantum technologies. The first part is dedicated to the analysis of causal structure, which…

Quantum Physics · Physics 2018-07-18 Mirjam Weilenmann

Finding exponential separation between quantum and classical information tasks is like striking gold in quantum information research. Such an advantage is believed to hold for quantum computing but is proven for quantum communication…

Quantum entanglement detection and characterization are crucial for various quantum information processes. Most existing methods for entanglement detection rely heavily on a complete description of the quantum state, which requires numerous…

Quantum Physics · Physics 2025-04-21 Rui Li , Shikun Zhang , Zheng Qin , Chunxiao Du , Yang Zhou , Zhisong Xiao

Entanglement in multipartite systems is a key resource for quantum information and communication protocols, making its verification in complex systems a necessity. Because an exact calculation of arbitrary entanglement probes is impossible,…

Quantum Physics · Physics 2018-09-18 Stefan Gerke , Werner Vogel , Jan Sperling

Unraveling the causal relationships among the execution of process activities is a crucial element in predicting the consequences of process interventions and making informed decisions regarding process improvements. Process discovery…

Artificial Intelligence · Computer Science 2025-01-15 Fabiana Fournier , Lior Limonad , Inna Skarbovsky , Yuval David