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Related papers: Spectral gap estimates for some block matrices

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The spectral and scattering theory is investigated for a generalization, to scattering metrics on two-dimensional compact manifolds with boundary, of the class of smooth potentials on the Euclidean plane which are homogeneous of degree zero…

Analysis of PDEs · Mathematics 2007-05-23 Andrew Hassell , Richard B. Melrose , András Vasy

Recently developed methods for PT-symmetric models can be applied to quantum-mechanical matrix and vector models. In matrix models, the calculation of all singlet wave functions can be reduced to the solution a one-dimensional PT-symmetric…

High Energy Physics - Theory · Physics 2008-11-26 Michael C. Ogilvie , Peter N. Meisinger

In this paper we propose and analyze an algorithm for identifying spectral gaps of a real symmetric matrix $A$ by simultaneously approximating the traces of spectral projectors associated with multiple different spectral slices. Our method…

Numerical Analysis · Mathematics 2025-09-09 Michele Benzi , Michele Rinelli , Igor Simunec

This paper reviews the 1994 proof that the spectral gap of Hamiltonian quantum systems capable of universal computation is uncomputable.

Quantum Physics · Physics 2016-02-19 Seth Lloyd

We compute the spectrum of quasinormal frequencies of five-dimensional black holes obtained in noncommutative geometry. In particular, we study scalar perturbations of a massive scalar field adopting the 6th order WKB approximation. We…

General Relativity and Quantum Cosmology · Physics 2019-12-24 Grigoris Panotopoulos , Ángel Rincón

We introduce a new concept of infinite quasi-exactly solvable models which are constructable through multi-parameter deformations of known exactly solvable ones. The spectral problem for these models admits exact solutions for infinitely…

High Energy Physics - Theory · Physics 2007-05-23 H. D. Doebner , K. Lazarow , A. G. Ushveridze

We calculate the probability to find exactly $n$ eigenvalues in a spectral interval of a large random $N \times N$ matrix when this interval contains $s \ll N$ eigenvalues on average. The calculations exploit an analogy to the problem of…

Condensed Matter · Physics 2009-10-22 M. M. Fogler , B. I. Shklovskii

The spectral statistics of non-Hermitian random matrices are of importance as a diagnostic tool for chaotic behavior in open quantum systems. Here, we investigate the statistical properties of singular values in non-Hermitian random…

Mesoscale and Nanoscale Physics · Physics 2023-10-19 Kohei Kawabata , Zhenyu Xiao , Tomi Ohtsuki , Ryuichi Shindou

When approximating elliptic problems by using specialized approximation techniques, we obtain large structured matrices whose analysis provides information on the stability of the method. Here we provide spectral and norm estimates for…

Numerical Analysis · Mathematics 2023-03-23 Armando Coco , Sven-Erik Ekström , Giovanni Russo , Stefano Serra-Capizzano , Santina Chiara Stissi

Statistical models on infinite graphs may exhibit inhomogeneous thermodynamic behaviour at macroscopic scales. This phenomenon is of geometrical origin and may be properly described in terms of spectral partitions into subgraphs with well…

Statistical Mechanics · Physics 2015-06-24 R. Burioni , D. Cassi , C. Destri

In this paper, we give upper and lower bounds for the spectral radius of a nonnegative irreducible matrix and characterize the equality cases. These bounds theoretically improve and generalize some known results of Duan et al.[X. Duan, B.…

Combinatorics · Mathematics 2013-10-22 Shu-Yu Cui , Gui-Xian Tian

We consider the spectrum of the almost Mathieu operator $H_\alpha$ with frequency $\alpha$ and in the case of the critical coupling. Let an irrational $\alpha$ be such that $|\alpha-p_n/q_n|<c q_n^{-\varkappa}$, where $p_n/q_n$,…

Spectral Theory · Mathematics 2016-11-23 I. Krasovsky

We show that in $\text{O}(D)$ invariant matrix theories containing a large number $D$ of complex or Hermitian matrices, one can define a $D\rightarrow\infty$ limit for which the sum over planar diagrams truncates to a tractable, yet…

High Energy Physics - Theory · Physics 2021-03-04 Frank Ferrari

We use super-spectral curve to investigate irregular conformal states of integer and half-odd integer rank. The spectral curve is the loop equation of supersymmetrized irregular matrix model. The case of integer rank corresponds to the…

High Energy Physics - Theory · Physics 2016-12-21 Dimitri Polyakov , Chaiho Rim

We study the spectral statistics of quantum (metric) graphs whose vertices are equipped with preferred orientation vertex conditions. When comparing their spectral statistics to those predicted by suitable random matrix theory ensembles,…

Spectral Theory · Mathematics 2025-08-08 Ram Band , Pavel Exner , Divya Goel , Aviya Strauss

We investigate determinantal varieties for symmetric matrices that have zero blocks along the main diagonal. In theoretical physics, these arise as Gram matrices for kinematic variables in quantum field theories. We study the ideals of…

Commutative Algebra · Mathematics 2026-05-19 Yassine El Maazouz , Bernd Sturmfels , Svala Sverrisdóttir

Finite-size criteria have emerged as an effective tool for deriving spectral gaps in higher-dimensional frustration-free quantum spin systems. We quantitatively improve the existing finite-size criteria by introducing a novel subsystem…

Mathematical Physics · Physics 2022-07-13 Marius Lemm , David Xiang

The unitary evolution maps in closed chaotic quantum graphs are known to have universal spectral correlations, as predicted by random matrix theory. In chaotic graphs with absorption the quantum maps become non-unitary. We show that their…

Chaotic Dynamics · Physics 2013-08-13 Boris Gutkin , Vladimir Al. Osipov

The concept of quasi-isometric embedding maps between $*$-algebras is introduced. We have obtained some basic results related to this notion and similar to quasi-isometric embedding maps on metric spaces, under some conditions, we give a…

Functional Analysis · Mathematics 2026-04-10 Ali Ebadian , Ali Jabbari

We show that random matrix models are a natural tool for understanding the appearance of a large gap in the microstate spectrum of black holes when there is a high degeneracy of states, in a variety of settings. While the most natural…

High Energy Physics - Theory · Physics 2025-08-01 Clifford V. Johnson , Mykhaylo Usatyuk
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