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相关论文: Missing levels in correlated spectra

200 篇论文

We study the accuracy and precision for estimating the fraction of observed levels $\varphi$ in quantum chaotic spectra through long-range correlations. We focus on the main statistics where theoretical formulas for the fraction of missing…

数据分析、统计与概率 · 物理学 2020-11-04 I. Casal , L. Muñoz , R. A. Molina

We study the observable properties of quantum systems which involve a quantum continuum as a subpart. We show in a very general way that in any system, which consists of at least two isolated states coupled to a continuum, the spectral…

强关联电子 · 物理学 2019-05-01 Nikolay Gnezdilov , Alexander Krikun , Koenraad Schalm , Jan Zaanen

Much effort has been spent on characterizing the spectrum of the non-backtracking matrix of certain classes of graphs, with special emphasis on the leading eigenvalue or the second eigenvector. Much less attention has been paid to the…

组合数学 · 数学 2020-07-29 Leo Torres

The performance of spectral clustering relies on the fluctuations of the entries of the eigenvectors of a similarity matrix, which has been left uncharacterized until now. In this letter, it is shown that the signal $+$ noise structure of a…

机器学习 · 统计学 2024-05-28 Hugo Lebeau , Florent Chatelain , Romain Couillet

In comparing the behavior of an energy spectrum to the predictions of random matrix theory one must transform the spectrum such that the averaged level spacing is constant, a procedure known as unfolding. Once energy spectrums belong to an…

无序系统与神经网络 · 物理学 2023-06-14 Richard Berkovits

The determination of absolute branching ratios for high-energy states in light nuclei is an important and useful tool for probing the underlying nuclear structure of individual resonances: for example, in establishing the tendency of an…

A pulsed source of entangled photons is desirable for some applications. Yet, such a source has intrinsic problems arising from the simultaneous arrival of the signal and noise photons to the detectors. These problems are analyzed and…

光学 · 物理学 2015-06-18 Mónica B. Agüero , Alejandro A. Hnilo , Marcelo G. Kovalsky

The technique of degree of randomness is used to model the correlations in sequences containing various subsignals and noise. Kolmogorov stochasticity parameter enables to quantify the randomness in number sequences and hence appears as an…

宇宙学与河外天体物理 · 物理学 2015-06-03 S. Sargsyan

Photon-based spectroscopies have had a significant impact on both fundamental science and applications by providing an efficient approach to investigate the microscopic physics of materials. Together with the development of synchrotron…

For a large class of linear neutral type systems the problem of eigenvalues and eigenvectors assignment is investigated, i.e. finding the system which has the given spectrum and almost all, in some sense, eigenvectors.

最优化与控制 · 数学 2013-04-17 Kateryna V. Sklyar , Rabah Rabah , Grigory M. Sklyar

In an electronic decay process followed by fragmentation the kinetic energy release and electron spectra can be measured. Classically they are the mirror image of each other, a fact which is often used in practice. Quantum expressions are…

量子物理 · 物理学 2015-05-30 Ying-Chih Chiang , Frank Otto , Hans-Dieter Meyer , Lorenz S. Cederbaum

The spectral statistics of nuclei undergo through the major forms of radioactive decays ((\alpha)(\beta^-), and(\beta^+) (or EC)) and also stable nuclei are investigated. With employing the MLE technique in the nearest neighbor spacing…

核理论 · 物理学 2012-09-25 M. A. Jafarizadeh , N. Fouladi , H. Sabri , B. Rashidian Maleki

This review article is devoted to application of precision molecular spectroscopy to studies of the possible spatial and temporal variations of the fundamental constants. Both astrophysical observations and laboratory experiments are…

原子物理 · 物理学 2009-07-18 V. V. Flambaum , M. G. Kozlov

Future neutrino-oscillation experiments are expected to bring definite answers to the questions of neutrino-mass hierarchy and violation of charge-parity symmetry in the lepton sector. To realize this ambitious program it is necessary to…

高能物理 - 唯象学 · 物理学 2017-05-15 Artur M Ankowski , Camillo Mariani

We consider interaction of a femtosecond light pulse with a one-dimensional photonic crystal with relaxing cubic nonlinearity in the regime of self-trapping. By use of numerical simulations, it is shown that, under certain conditions, the…

光学 · 物理学 2011-12-01 Denis Novitsky

In a mixed generalized linear model, the goal is to learn multiple signals from unlabeled observations: each sample comes from exactly one signal, but it is not known which one. We consider the prototypical problem of estimating two…

统计理论 · 数学 2026-01-12 Yihan Zhang , Marco Mondelli , Ramji Venkataramanan

We carry out a numerical study of fluctuations in the spectrum of regular graphs. Our experiments indicate that the level spacing distribution of a generic k-regular graph approaches that of the Gaussian Orthogonal Ensemble of random matrix…

高能物理 - 理论 · 物理学 2007-05-23 D. Jakobson , S. D. Miller , I. Rivin , Z. Rudnick

We derive an expression for the nearest-neighbor spacing distribution $P(s)$ of the energy levels of quantum systems with intermediate dynamics between regularity and chaos and missing levels due to random experimental errors. The…

量子物理 · 物理学 2023-06-08 María Hita-Pérez , Laura Muñoz , Rafael A. Molina

We discuss the phenomenon of universal fluctuations in mesoscopic systems and nuclei. For this purpose we use Random Matrix Theory (RMT). The statistical $S$-matrix is used to obtain the physical observables in the case of Quantum Dots,…

介观与纳米尺度物理 · 物理学 2018-05-29 M. S. Hussein , J. G. G. S. Ramos

Interpretation and understanding of the evidence for neutrino oscillations depends on knowledge of the atmospheric neutrino beam. In this talk I assess how well various features are known. The goal is to determine to what extent…

高能物理 - 唯象学 · 物理学 2011-05-12 T. K. Gaisser