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Related papers: Random-Matrix Approach to RPA equations. I

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We consider the dynamics of bodies with "active" microstructure described by vector-valued phase fields. For waves with time-varying amplitude, the associated evolution equation involves a matrix that can be non-normal, depending on the…

Mathematical Physics · Physics 2025-02-18 Michele Benzi , Daniele La Pegna , Paolo Maria Mariano

Economic and ecological models can be extremely complex, with a large number of agents/species each featuring multiple interacting dynamical quantities. In an attempt to understand the generic stability properties of such systems, we define…

Disordered Systems and Neural Networks · Physics 2025-04-15 Nirbhay Patil , Fabian Aguirre-Lopez , Jean-Philippe Bouchaud

The study of dissipation and decoherence in generic open quantum systems recently led to the investigation of spectral and steady-state properties of random Lindbladian dynamics. A natural question is then how realistic and universal those…

Statistical Mechanics · Physics 2020-10-22 Lucas Sá , Pedro Ribeiro , Tankut Can , Tomaž Prosen

We describe a random matrix approach that can provide generic and readily soluble mean-field descriptions of the phase diagram for a variety of systems ranging from QCD to high-T_c materials. Instead of working from specific models, phase…

High Energy Physics - Phenomenology · Physics 2015-05-28 Benoit Vanderheyden , A D Jackson

We introduce a random matrix framework for studying statistical-mechanical lattice systems through spectral observables. Equilibrium configurations sampled from a Boltzmann measure are mapped to matrix ensembles whose covariance structure…

Disordered Systems and Neural Networks · Physics 2026-05-21 Yaprak Önder , Abbas Ali Saberi , Roderich Moessner

The spectra of random feature matrices provide essential information on the conditioning of the linear system used in random feature regression problems and are thus connected to the consistency and generalization of random feature models.…

Machine Learning · Statistics 2022-12-13 Zhijun Chen , Hayden Schaeffer , Rachel Ward

A system with many degrees of freedom can be characterized by a covariance matrix; principal components analysis (PCA) focuses on the eigenvalues of this matrix, hoping to find a lower dimensional description. But when the spectrum is…

Biological Physics · Physics 2017-04-26 Serena Bradde , William Bialek

We consider quantum systems with a chaotic classical limit that depend on an external parameter, and study correlations between the spectra at different parameter values. In particular, we consider the parametric spectral form factor…

Chaotic Dynamics · Physics 2010-03-09 Jack Kuipers , Martin Sieber

Principal component analysis (PCA) aims at estimating the direction of maximal variability of a high-dimensional dataset. A natural question is: does this task become easier, and estimation more accurate, when we exploit additional…

Information Theory · Computer Science 2014-06-19 Andrea Montanari , Emile Richard

Covariance matrix estimation and principal component analysis (PCA) are two cornerstones of multivariate analysis. Classic textbook solutions perform poorly when the dimension of the data is of a magnitude similar to the sample size, or…

Statistics Theory · Mathematics 2014-06-25 Olivier Ledoit , Michael Wolf

The full spectrum of transfer matrices of the general eight-vertex model on a square lattice is obtained by numerical diagonalization. The eigenvalue spacing distribution and the spectral rigidity are analyzed. In non-integrable regimes we…

Condensed Matter · Physics 2009-10-28 Hendrik Meyer , Jean-Christian Anglès d'Auriac , Henrik Bruus

The class of norm-dependent Random Matrix Ensembles is studied in the presence of an external field. The probability density in those ensembles depends on the trace of the squared random matrices, but is otherwise arbitrary. An exact…

Mathematical Physics · Physics 2009-11-11 Thomas Guhr

We investigate spectral properties of quantum graphs in the form of a periodic chain of rings with a connecting link between each adjacent pair, assuming that wave functions at the vertices are matched through conditions manifestly…

Mathematical Physics · Physics 2022-07-12 Marzieh Baradaran , Pavel Exner , Milos Tater

Random matrix theory allows for the deduction of stability criteria for complex systems using only a summary knowledge of the statistics of the interactions between components. As such, results like the well-known elliptical law are…

Disordered Systems and Neural Networks · Physics 2023-11-06 Lyle Poley , Tobias Galla , Joseph W. Baron

By coupling a doorway state to a see of random background states, we develop the theory of doorway states in the framework of the random-phase approximation (RPA). Because of the symmetry of the RPA equations, that theory is radically…

Nuclear Theory · Physics 2015-06-22 A. De Pace , A. Molinari , H. A. Weidenmueller

Estimating the eigenvalues of a population covariance matrix from a sample covariance matrix is a problem of fundamental importance in multivariate statistics; the eigenvalues of covariance matrices play a key role in many widely…

Statistics Theory · Mathematics 2007-06-13 Noureddine El Karoui

The Random Orthogonal Model (ROM) of Marinari-Parisi-Ritort [MPR1,MPR2] is a model of statistical mechanics where the couplings among the spins are defined by a matrix chosen randomly within the orthogonal ensemble. It reproduces the most…

Disordered Systems and Neural Networks · Physics 2007-05-23 M. Degli Esposti , C. Giardina' , S. Graffi

Multiple matrix sampling is a survey methodology technique that randomly chooses a relatively small subset of items to be presented to survey respondents for the purpose of reducing respondent burden. The data produced are missing…

Methodology · Statistics 2017-10-03 Stanislav Kolenikov , Heather Hammer

We consider an ensemble of $2\times 2$ normal matrices with complex entries representing operators in the quantum mechanics of 2 - level parity-time reversal (PT) symmetric systems. The randomness of the ensemble is endowed by obtaining…

Mathematical Physics · Physics 2025-01-14 Stalin Abraham , A. Bhagwat , Sudhir Ranjan Jain

Pattern formation in the classical and fractional Schnakenberg equations is studied to understand the nonlocal effects of anomalous diffusion. Starting with linear stability analysis, we find that if the activator and inhibitor have the…

Pattern Formation and Solitons · Physics 2021-06-21 Hatim Khudhair , Yanzhi Zhang , Nobuyuki Fukawa