Results 1 to 10 of about 841 (144)
Entropy, 2021 Given the algebra of observables of a quantum system subject to selection rules, a state can be represented by different density matrices. As a result, different von Neumann entropies can be associated with the same state.
Paolo Facchi +2 more
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Algebras Generated by Finite Subgroups of Unitary Groups
Journal of Harbin University of Science and Technology, 2021 Group representation theory is one of the most powerful tools to study groups. The unitary group is an important research branch of group theories. We study a class of algebraic structures generated by unitary groups，and we prove that Alg( H) is a von ...
LUO Lai-zhen, LI Xing-hua, TAO Yuan-hong
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Steering projections in von Neumann algebras [PDF]
Opuscula Mathematica, 2015 A steering projection of an arbitrary von Neumann algebra is introduced. It is shown that a steering projection always exists and is unique (up to Murray-von Neumann equivalence).
Adam Wegert
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Orthogonalization of Positive Operator Valued Measures
Comptes Rendus. Mathématique, 2022 We show that a partition of the unity (or POVM) on a Hilbert space that is almost orthogonal is close to an orthogonal POVM in the same von Neumann algebra. This generalizes to infinite dimension previous results in matrix algebras by Kempe–Vidick and Ji–
de la Salle, Mikael
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Information loss, mixing and emergent type III1 factors
Journal of High Energy Physics, 2023 A manifestation of the black hole information loss problem is that the two-point function of probe operators in a large Anti-de Sitter black hole decays in time, whereas, on the boundary CFT, it is expected to be an almost periodic function of time.
Keiichiro Furuya +3 more
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On the isomorphism class of $q$-Gaussian W$^\ast $-algebras for infinite variables
Comptes Rendus. Mathématique, 2023 Let $M_q(H_{\mathbb{R}})$ be the $q$-Gaussian von Neumann algebra associated with a separable infinite dimensional real Hilbert space $H_{\mathbb{R}}$ where $-1 < q < 1$. We show that $M_q(H_{\mathbb{R}}) \lnot \simeq M_0(H_{\mathbb{R}})$ for $-1 < q \ne
Caspers, Martijn
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Derivations with values in noncommutative symmetric spaces
Comptes Rendus. Mathématique, 2023 Let $E=E(0,\infty )$ be a symmetric function space and $E(\mathcal{M},\tau )$ be the noncommutative symmetric space corresponding to $E(0,\infty )$ associated with a von Neumann algebra with a faithful normal semifinite trace.
Huang, Jinghao, Sukochev, Fedor
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Logical Characterization of Contextual Hidden-Variable Theories based on Quantum Set Theory
Electronic Proceedings in Theoretical Computer Science, 2023 While non-contextual hidden-variable theories are proved to be impossible, contextual ones are possible. In a contextual hidden-variable theory, an observable is called a beable if the hidden-variable assigns its value in a given measurement context ...
Ozawa, Masanao
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Maximum Entropy Models for Quantum Systems
Entropy, 2016 We show that for a finite von Neumann algebra, the states that maximise Segal’s entropy with a given energy level are Gibbs states. This is a counterpart of the classical result for the algebra of all bounded linear operators on a Hilbert space and von ...
Andrzej Łuczak +2 more
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Real-space RG, error correction and Petz map
Journal of High Energy Physics, 2022 There are two parts to this work: first, we study the error correction properties of the real-space renormalization group (RG). The long-distance operators are the (approximately) correctable operators encoded in the physical algebra of short-distance ...
Keiichiro Furuya +2 more
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