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We show that the non-locality together with the statistical character makes the world statistically separable. The super-luminal signal transmission is impossible. The quantum theory is therefore consistent with the relativity and the…

Quantum Physics · Physics 2009-02-10 Qi-Ren Zhang

The principle of `absoluteness of cause' (AC) assumes the cause-effect relation to be observer independent and is a distinct assertion than prohibiting occurrence of any causal loop. Here, we study implication of this novel principle to…

Quantum Physics · Physics 2021-09-28 Anandamay Das Bhowmik , Preeti Parashar , Guruprasad Kar , Manik Banik

Bell non-local correlations cannot be naturally explained in a fixed causal structure. This serves as a motivation for considering models where no global assumption is made beyond logical consistency. The assumption of a fixed causal order…

Quantum Physics · Physics 2016-04-06 Ämin Baumeler , Stefan Wolf

The fact that closed timelike curves (CTCs) are permitted by general relativity raises the question as to how quantum systems behave when time travel to the past occurs. Research into answering this question by utilising the quantum circuit…

Quantum Physics · Physics 2014-10-13 John-Mark A. Allen

The strong exponential-time hypothesis (SETH) is a commonly used conjecture in the field of complexity theory. It states that CNF formulas cannot be analyzed for satisfiability with a speedup over exhaustive search. This hypothesis and its…

Quantum Physics · Physics 2019-11-15 Harry Buhrman , Subhasree Patro , Florian Speelman

We consider gravity in 2+1 dimensions in presence of extended stationary sources with rotational symmetry. We prove by direct use of Einstein's equations that if i) the energy momentum tensor satisfies the weak energy condition, ii) the…

High Energy Physics - Theory · Physics 2009-10-22 P. Menotti , D. Seminara

We identify a new class of non-Hermitian causal processes that produce statistically significant temporal correlations invisible to conventional spectral methods. Using a generative model with a strictly causal memory kernel, we demonstrate…

Statistical Mechanics · Physics 2026-04-01 Mario J. Pinheiro

We consider a Parity-time (PT) invariant non-Hermitian quasi-exactly solvable (QES) potential which exhibits PT phase transition. We numerically study this potential in a complex plane classically to demonstrate different quantum effects.…

Quantum Physics · Physics 2015-09-25 Bhabani Prasad Mandal , Sushant S. Mahajan

Structural Equation Models (SEM) are the standard approach to representing causal dependencies between variables in causal models. In this paper we propose a new interpretation of SEMs when reasoning about Actual Causality, in which SEMs…

Artificial Intelligence · Computer Science 2025-12-23 Maksim Gladyshev , Natasha Alechina , Mehdi Dastani , Dragan Doder , Brian Logan

Existing work on quantum causal structure assumes that one can perform arbitrary operations on the systems of interest. But this condition is often not met. Here, we extend the framework for quantum causal modelling to situations where a…

Quantum Physics · Physics 2023-06-07 Nick Ormrod , Augustin Vanrietvelde , Jonathan Barrett

This study examines the formulation of a singularity theorem for timelike curves including torsion, and establishes the foundational framework necessary for its derivation. We begin by deriving the relative acceleration for an arbitrary…

General Relativity and Quantum Cosmology · Physics 2024-09-30 Armin van de Venn , Ujjwal Agarwal , David Vasak

It has long been recognized that certain quantum correlations are incompatible with particular assumption about classical causal structure. Given a causal structure of unknown classicality, the presence of such correlations certifies the…

Quantum Physics · Physics 2020-08-19 Thomas C. Fraser , Elie Wolfe

A recently proposed algebraic representation of the causal set model of the small-scale structure of space-time of Sorkin et al. is briefly reviewed and expanded. The algebraic model suggested, called quantum causal set, is physically…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ioannis Raptis

The constraints arising for a general set of causal relations, both classically and quantumly, are still poorly understood. As a step in exploring this question, we consider a coherently controlled superposition of "direct-cause" and…

Quantum Physics · Physics 2018-01-11 Adrien Feix , Časlav Brukner

Demonstrations of quantum entanglement which confirm the violation of Bell's inequality indicate that under certain conditions action at a distance is possible. This consequence seems to contradict the relativistic principle of causality,…

Quantum Physics · Physics 2018-11-02 Yoram Kirsh

In this paper we consider a claim that in the natural world there is no fact of the matter about the spatio-temporal separation of events. In order to make sense of such a notion and construct useful models of the world, it is proposed to…

Neurons and Cognition · Quantitative Biology 2024-04-18 Bartosz Jura

Wave--particle duality is a cornerstone of quantum mechanics, traditionally formulated under definite causal order. We investigate how complementarity is modified when the temporal order of operations is coherently superposed, as in the…

Quantum Physics · Physics 2026-03-31 Mohd Asad Siddiqui , Md Qutubuddin , Tabish Qureshi

The possible existence of closed timelike curves (CTCs) draws attention to fundamental questions about what is physically possible and what is not. An example is the "no cloning theorem" in quantum mechanics, which states that no physical…

Quantum Physics · Physics 2015-06-19 D. Ahn , T. C. Ralph , R. B. Mann

The problem of using observed correlations to infer causal relations is relevant to a wide variety of scientific disciplines. Yet given correlations between just two classical variables, it is impossible to determine whether they arose from…

The standard formulation of quantum theory assumes a predefined notion of time. This is a major obstacle in the search for a quantum theory of gravity, where the causal structure of space-time is expected to be dynamical and fundamentally…

Quantum Physics · Physics 2016-07-29 Ognyan Oreshkov , Nicolas J. Cerf