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We present a novel approach using neural networks to recover X-ray spectral model parameters and quantify uncertainties, balancing accuracy and computational efficiency against traditional frequentist and Bayesian methods. Frequentist…

Instrumentation and Methods for Astrophysics · Physics 2025-04-09 A. Tutone , A. Anitra , E. Ambrosi , R. La Placa , A. D'Aì , C. Pinto , M. Del Santo , F. Pintore , A. Pagliaro , A. Anzalone , T. Di Salvo , R. Iaria , L. Burderi , A. Sanna

Random matrix ensembles (RME) of quantum statistical Hamiltonian operators, {\em e.g.} Gaussian random matrix ensembles (GRME) and Ginibre random matrix ensembles (Ginibre RME), found applications in literature in study of following quantum…

Statistical Mechanics · Physics 2007-05-23 Maciej M. Duras

The information spectrum approach gives general formulae for optimal rates of codes in many areas of information theory. In this paper the quantum spectral divergence rates are defined and properties of the rates are derived. The entropic…

Quantum Physics · Physics 2007-07-13 Garry Bowen , Nilanjana Datta

We consider the probability of having two intervals (gaps) without eigenvalues in the bulk scaling limit of the Gaussian Unitary Ensemble of random matrices. We describe uniform asymptotics for the transition between a single large gap and…

Functional Analysis · Mathematics 2020-03-19 Benjamin Fahs , Igor Krasovsky

A spectral average which generalises the local spacing distribution of the eigenvalues of random $ N\times N $ hermitian matrices in the bulk of their spectrum as $ N\to\infty $ is known to be a $\tau$-function of the fifth Painlev\'e…

Classical Analysis and ODEs · Mathematics 2009-11-13 A. V. Kitaev , N. S. Witte

We propose a redshift estimator for the long ($T_{90} > 20$) gamma-ray bursts (GRBs) observed by the BATSE. It is based on an empirical relation between the redshift and the power-law index of power density spectra (PDSs) of the observed…

Astrophysics · Physics 2007-05-23 Heon-Young Chang , Suk-Jin Yoon , Chul-Sung Choi

Mixed state ensembles such as the Bures-Hall and Hilbert-Schmidt measure are probability distributions that characterise the statistical properties of random density matrices and can be used to determine the typical features of mixed…

Quantum Physics · Physics 2026-03-31 Harry J. D. Miller

A nonlinear model with response variable missing at random is studied. In order to improve the coverage accuracy, the empirical likelihood ratio (EL) method is considered. The asymptotic distribution of EL statistic and also of its…

Methodology · Statistics 2010-05-19 Gabriela Ciuperca

Banded random matrices were introduced as a more realistic alternative to full random matrices for describing the spectral statistics of heavy nuclei. Initially considered by Wigner, they have since become a paradigmatic model for…

Disordered Systems and Neural Networks · Physics 2025-06-10 Adway Kumar Das , Anandamohan Ghosh , Lea F. Santos

The use of rapidity gaps is proposed as a measure of the spatial pattern of an event. When the event multiplicity is low, the gaps between neighboring particles carry far more information about an event than multiplicity spikes, which may…

High Energy Physics - Phenomenology · Physics 2009-10-31 Rudolph C. Hwa , Qing-hui Zhang

In this paper we discuss reduced order models for the approximation of parametric eigenvalue problems. In particular, we are interested in the presence of intersections or clusters of eigenvalues. The singularities originating by these…

Numerical Analysis · Mathematics 2024-07-11 Daniele Boffi , Abdul Halim , Gopal Priyadarshi

We describe the distribution of the first finite number of eigenvalues in a newly-forming band of the spectrum of the random Hermitean matrix model. The method is rigorously based on the Riemann-Hilbert analysis of the corresponding…

Mathematical Physics · Physics 2016-09-08 M. Bertola , S. Y. Lee

The work presents a proof of convergence of the density of energy levels to a Gaussian distribution for a wide class of quadratic forms of Fermi operators. This general result applies also to quadratic operators with disorder, e.g.,…

Mathematical Physics · Physics 2017-06-28 Fabio Deelan Cunden , Anna Maltsev , Francesco Mezzadri

Recent measurements of resonance widths for low-energy neutron scattering off heavy nuclei show large deviations from the standard Porter-Thomas distribution. We propose a new resonance width distribution based on the random matrix theory…

Nuclear Theory · Physics 2012-10-09 Gavriil Shchedrin , Vladimir Zelevinsky

The excess entropy of restricted primitive model electrolytes is calculated using a potential based approach through the symmetric Poisson-Boltzmann and the modified Poisson-Boltzmann theories. The theories are utilized in conjunction with…

Statistical Mechanics · Physics 2025-04-01 S. Lamperski , L. B. Bhuiyan , C. W. Outhwaite , R. Gorniak

An exact method that analytically provides transfer matrices in finite networks of quasicrystalline approximants of any dimensionality is discussed. We use these matrices in two ways: a) to exactly determine the band structure of an…

Condensed Matter · Physics 2016-08-31 K. Moulopoulos , S. Roche

This paper proposes a very simple perturbative technique to calculate the low-lying eigenvalues and eigenstates of a parity-symmetric quantum-mechanical potential. The technique is to solve the time-independent Schroedinger eigenvalue…

Quantum Physics · Physics 2015-06-18 Carl M. Bender , Hugh F. Jones

We consider identical quantum bosons with weak contact interactions in a two-dimensional isotropic harmonic trap. When the interactions are turned off, the energy levels are equidistant and highly degenerate. At linear order in the coupling…

Quantum Gases · Physics 2019-08-21 Ben Craps , Marine De Clerck , Oleg Evnin , Surbhi Khetrapal

A one-parameter random matrix model is proposed for describing the statistics of the local amplitudes and phases of electron eigenfunctions in a mesoscopic quantum dot in an arbitrary magnetic field. Comparison of the statistics obtained…

Condensed Matter · Physics 2009-10-28 E. Kanzieper , V. Freilikher

Temperature variations of the heat capacity (C) are studied in a low temperature regime for 2D-, and 3D-systems with N~100-10000 treated as a canonical ensemble of N-noninteracting fermions. The analysis of C is performed by introducing…

Mesoscale and Nanoscale Physics · Physics 2008-12-01 N. K. Kuzmenko , V. M. Mikhajlov