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Related papers: Almost sure convergence in quantum spin glasses

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We study the density of states measure for some class of random unitary band matrices and prove a Thouless formula relating it to the associated Lyapunov exponent. This class of random matrices appears in the study of the dynamical…

Mathematical Physics · Physics 2015-06-26 Alain Joye

The eigenstates of a quantum spin glass Hamiltonian with long-range interaction are examined from the point of view of localisation and entanglement. In particular, low particle sectors are examined and an anomalous family of eigenstates is…

Quantum Physics · Physics 2017-10-18 Arun Kannawadi , Auditya Sharma , Arul Lakshminarayan

The Wasserstein distance between two probability measures on a metric space is a measure of closeness with applications in statistics, probability, and machine learning. In this work, we consider the fundamental question of how quickly the…

Probability · Mathematics 2017-07-04 Jonathan Weed , Francis Bach

A new entanglement measure, the multiple entropy measures (MEMS), is proposed to quantify quantum entanglement of multi-partite quantum state. The MEMS is vector-like with $m=[N/2]$, the integer part of $N/2$, components: $[S_1, S_2,...,…

Quantum Physics · Physics 2007-06-23 Dan Liu , Xin Zhao , Gui Lu Long

We investigate random density matrices obtained by partial tracing larger random pure states. We show that there is a strong connection between these random density matrices and the Wishart ensemble of random matrix theory. We provide…

Quantum Physics · Physics 2009-05-14 Ion Nechita

We consider ensembles of bipartite states resulting from a random passive Gaussian unitary applied to a fiducial pure Gaussian state. We show that the symplectic spectra of the reduced density operators concentrate around that of a thermal…

Quantum Physics · Physics 2019-12-02 Motohisa Fukuda , Robert Koenig

The spectral densities of ensembles of non-Hermitian sparse random matrices are analysed using the cavity method. We present a set of equations from which the spectral density of a given ensemble can be efficiently and exactly calculated.…

Disordered Systems and Neural Networks · Physics 2009-11-13 Tim Rogers , Isaac Perez Castillo

To establish a unified framework for studying both discrete and continuous coupling distributions, we introduce the {\it binomial} spin glass, a class of models where the couplings are sums of $m$ identically distributed Bernoulli random…

Disordered Systems and Neural Networks · Physics 2018-08-29 Mohammad-Sadegh Vaezi , Gerardo Ortiz , Martin Weigel , Zohar Nussinov

We investigate the spectral statistics of the difference of two density matrices, each of which is independently obtained by partially tracing a random bipartite pure quantum state. We first show how a closed-form expression for the exact…

Mathematical Physics · Physics 2016-12-12 José Mejía , Camilo Zapata , Alonso Botero

Random Quantum States are presently of interest in the fields of quantum information theory and quantum chaos. Moreover, a detailed study of their properties can shed light on some foundational issues of the quantum statistical mechanics…

Quantum Physics · Physics 2010-01-07 Barbara Fresch , Giorgio J. Moro

Quantum state diffusion is a framework within which measurement may be described as the continuous and gradual collapse of a quantum system to an eigenstate as a result of interaction with its environment. The irreversible nature of the…

Quantum Physics · Physics 2025-09-18 Sophia M. Walls , Adam Bloss , Ian J. Ford

The measurement of a spin-$\half$ is modeled by coupling it to an apparatus, that consists of an Ising magnetic dot coupled to a phonon bath. Features of quantum measurements are derived from the dynamical solution of the measurement,…

Quantum Physics · Physics 2017-08-23 Armen E. Allahverdyan , Roger Balian , Theo M. Nieuwenhuizen

We study the spectrum of a system of coupled disordered harmonic oscillators in the thermodynamic limit. This Euclidean random matrix ensemble has been suggested as model for the low-temperature vibrational properties of glass. Exact…

Disordered Systems and Neural Networks · Physics 2024-01-22 Philipp Baumgärtel , Florian Vogel , Matthias Fuchs

This paper studies convergence of empirical measures smoothed by a Gaussian kernel. Specifically, consider approximating $P\ast\mathcal{N}_\sigma$, for $\mathcal{N}_\sigma\triangleq\mathcal{N}(0,\sigma^2 \mathrm{I}_d)$, by…

Statistics Theory · Mathematics 2020-05-04 Ziv Goldfeld , Kristjan Greenewald , Yury Polyanskiy , Jonathan Weed

We investigate the spectral and localization properties of unmagnetized Heisenberg-Mattis spin glasses, in space dimensionalities $d=2$ and 3, at T=0. We use numerical transfer-matrix methods combined with finite-size scaling to calculate…

Statistical Mechanics · Physics 2007-05-23 S. L. A. de Queiroz , R. B. Stinchcombe

We introduce an effective field theory for the vicinity of a zero temperature quantum transition between a metallic spin glass (``spin density glass'') and a metallic quantum paramagnet. Following a mean field analysis, we perform a…

Condensed Matter · Physics 2009-10-28 Subir Sachdev , N. Read , R. Oppermann

In quantum mechanics, wave functions and density matrices represent our knowledge about a quantum system and give probabilities for the outcomes of measurements. If the combined dynamics and measurements on a system lead to a density matrix…

Quantum Physics · Physics 2016-12-07 D. Tan , M. Naghiloo , K. Mølmer , K. W. Murch

A gauge-invariant C*-system is obtained as the fixed point subalgebra of the infinite tensor product of full matrix algebras under the tensor product unitary action of a compact group. In the paper, thermodynamics is studied on such systems…

Operator Algebras · Mathematics 2009-11-10 N. Akiho , F. Hiai , D. Petz

We study the properties of a non-Gaussian density matrix for a O(N) scalar field in the context of the incomplete description picture. This is of relevance for studies of decoherence and entropy production in quantum field theory. In…

Quantum Physics · Physics 2011-06-13 F. Gautier , J. Serreau

This letter generalizes the expression for the average fidelity of single qubits, as found by Bowdrey et al., to the case of n qubits. We use a simple algebraic approach with basis elements for the density-matrix expansion expressed as…

Quantum Physics · Physics 2009-11-13 R. Cabrera , W. E. Baylis