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Related papers: Contextuality with a Small Number of Observables

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This paper is the first of several parts introducing a new powerful algebra: the algebra of the pseudo-observables. This is a C*-algebra whose set is formed by formal expressions involving observables. The algebra is constructed by applying…

Quantum Physics · Physics 2025-08-21 Edoardo Piparo

Recently, quantum contextuality has been proved to be the source of quantum computation's power. That, together with multiple recent contextual experiments, prompts improving the methods of generation of contextual sets and finding their…

Quantum Physics · Physics 2019-05-07 Mladen Pavicic , Norman D. Megill

The Kochen-Specker theorem rules out models of quantum theory wherein projective measurements are assigned outcomes deterministically and independently of context. This notion of noncontextuality is not applicable to experimental…

Quantum Physics · Physics 2018-05-11 Ravi Kunjwal , Robert W. Spekkens

We classify the sets of natural numbers $n$ for which certain dynamical systems $(X,f)$ on a compact metric space $X$ have a periodic point of (least) period $n$. Interest in this question dates back to Sharkovskii's theorem for continuous…

Dynamical Systems · Mathematics 2026-04-27 Huub de Jong

Composing two representations of the general linear groups gives rise to Littlewood's (outer) plethysm. On the level of characters, this poses the question of finding the Schur expansion of the plethysm of two Schur functions. A…

Combinatorics · Mathematics 2025-03-20 Laura Colmenarejo , Rosa Orellana , Franco Saliola , Anne Schilling , Mike Zabrocki

Combining the tools of geometric analysis with properties of Jordan angles and angle space distributions, we derive a spherical and a Euclidean Bernstein theorem for minimal submanifolds of arbitrary dimension and codimension, under the…

Differential Geometry · Mathematics 2014-05-26 J. Jost , Y. L. Xin , Ling Yang

The Kochen-Specker theorem is a fundamental result in quantum foundations that has spawned massive interest since its inception. We show that within every Kochen-Specker graph, there exist interesting subgraphs which we term $01$-gadgets,…

A physical applicability of normed split-algebras, such as hyperbolic numbers, split-quaternions and split-octonions is considered. We argue that the observable geometry can be described by the algebra of split-octonions. In such a picture…

High Energy Physics - Theory · Physics 2007-05-23 Merab Gogberashvili

We find many tight codes in compact spaces, i.e., optimal codes whose optimality follows from linear programming bounds. In particular, we show the existence (and abundance) of several hitherto unknown families of simplices in quaternionic…

Metric Geometry · Mathematics 2016-07-20 Henry Cohn , Abhinav Kumar , Gregory Minton

We present a new and feasible test proving quantum contextuality in four-dimensional Hiltbert space. In our scheme, a contradiction between quantum mechanics and noncontextual hidden variables is revealed through the measurement statistics…

Quantum Physics · Physics 2008-06-27 Yoshihiro Nambu

The non-classicality of single quantum systems can be formalised using the notion of contextuality. But can contextuality be convincingly demonstrated in an experiment, without reference to the quantum formalism? The operational approach to…

Quantum Physics · Physics 2019-04-19 Matthew F. Pusey , Lídia del Rio , Bettina Meyer

Theorems crucial in elementary real function theory have proofs in which compactness arguments are used. Despite the introduction in relatively recent literature of each new highly elegant compactness argument, or of an equivalent, this…

Classical Analysis and ODEs · Mathematics 2025-10-28 Rafael Cantuba

Compatibility between the realist tenants of value-definiteness and causality is called into question by several realism impossibility proofs in which their formal elements are shown to conflict. We review how this comes about in the…

Quantum Physics · Physics 2007-05-23 Ken Williams

Minimal surfaces and domain walls play important roles in various contexts of spacetime physics as well as material science. In this paper, we first review the Bernstein conjecture, which asserts that a plane is the only globally well…

High Energy Physics - Theory · Physics 2009-09-28 Gary W. Gibbons , Kei-ichi Maeda , Umpei Miyamoto

Contextuality is regarded as a non-classical feature, challenging our everyday intuition; quantum contextuality is currently seen as a resource for many applications in quantum computation, being responsible for quantum advantage over…

Quantum Physics · Physics 2020-12-16 Roberto D. Baldijao , Marcelo Terra Cunha

We combine several mini miracles to achieve an elementary understanding of infinite loop spaces and very effective spectra in the algebro-geometric setting of motivic homotopy theory. Our approach combines $\Gamma$-spaces and framed…

Algebraic Geometry · Mathematics 2022-04-22 Grigory Garkusha , Ivan Panin , Paul Arne Østvær

Quantum mechanics implies that not all physical properties can be simultaneously well defined, such as the momentum and position due to Heisenberg uncertainty principle. Some alternative theories have been explored, notably the…

Quantum Physics · Physics 2012-09-18 Xin-Yu Pan , Yan-Chun Chang , Gang-Qin Liu , Heng Fan

We show that a reduced form of the structural requirements for deterministic hidden variables used in Bell-Kochen-Specker theorems is already sufficient for the no-go results. Those requirements are captured by the following principle: an…

Quantum Physics · Physics 2015-06-22 James D. Malley , Arthur Fine

Contextuality is a fundamental marker of quantum non-classicality, which has emerged as a key resource for quantum computational advantage in multiple settings. Many such results hinge specifically on contextuality witnessed through Pauli…

Quantum Physics · Physics 2025-02-06 Raman Choudhary , Rui Soares Barbosa

Kent [quant-ph/9906006] has constructed a hidden variable theory by taking the finite precision of physical measurements into account. But its claim to noncontextuality has been queried, and it shown here that there is a particularly simple…

Quantum Physics · Physics 2007-05-23 C. F. Boyle , R. L. Schafir