Results 11 to 20 of about 3,060 (235)
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 of Murray–von Neumann algebras [PDF]
Journal für die reine und angewandte Mathematik (Crelles Journal), 2019 AbstractIn this paper, we answer in the affirmative the long-standing conjecture that the first cohomology group of the Murray–von Neumann algebraS(ℳ){S(\mathcal{M})}of all operators affiliated with a typeII1{\mathrm{II}_{1}}von Neumann algebraℳ{\mathcal{M}}is 0. That is, we show that all derivations ofS(ℳ){S(\mathcal{M})}are inner.
Aleksey Ber +2 more
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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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On the geometry of von Neumann algebra preduals [PDF]
, 2014 Let M be a von Neumann algebra and let M⋆ be its (unique) predual. We study when for every φ∈M⋆ there exists ψ∈M⋆ solving the equation ∥φ±ψ∥=∥φ∥=∥ψ∥. This is the case when M does not contain type I nor type III1 factors as direct summands and it is false
Ueda, Yoshimichi, Martín, Miguel
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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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