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We undertake a detailed analysis of ergodicity for homogeneous discrete-time quantum walks on the integer lattice. The most significant result of our paper holds in dimension one, and gives a complete equivalence between the absolutely…

Mathematical Physics · Physics 2026-04-22 Kiran Kumar , Mostafa Sabri

We exhibit d-dimensional limit-periodic Schrodinger operators that are uniformly localized in the strongest sense possible. That is, for each of these operators, there is a uniform exponential decay rate such that every element of the hull…

Spectral Theory · Mathematics 2012-07-26 David Damanik , Zheng Gan

This paper investigates first-order variable metric backward forward dynamical systems associated with monotone inclusion and convex minimization problems in real Hilbert space. The operators are chosen so that the backward-forward…

Optimization and Control · Mathematics 2021-06-15 Pankaj Gautam , D. R. Sahu , J. C. Yao

We study statistical properties of matrix elements of observables written in the energy eigenbasis and truncated to small microcanonical windows. We present numerical evidence indicating that for all few body operators in chaotic many-body…

Statistical Mechanics · Physics 2025-06-10 Jiaozi Wang , Jonas Richter , Mats H. Lamann , Robin Steinigeweg , Jochen Gemmer , Anatoly Dymarsky

We consider the empirical eigenvalue distribution of an $m\times m$ principle submatrix of an $n\times n$ random unitary matrix distributed according to Haar measure. Earlier work of Petz and R\'effy identified the limiting spectral measure…

Probability · Mathematics 2019-04-12 Elizabeth Meckes , Kathryn Stewart

We investigate the statistical properties of the scattering matrix $S$ describing the electron transport through quasi-one dimensional disordered systems. For weak disorder (metallic regime), the energy dependence of the phase shifts of $S$…

Mesoscale and Nanoscale Physics · Physics 2009-10-30 E. R. Mucciolo , R. A. Jalabert , J. -L. Pichard

In this paper we work with the approximation of unitary groups of operators of the form $e^{-itH}$ where $H\in\mathscr{L}(\mathcal{H})$ is the Hamiltonian of a given quantum dynamical system modeled in the discretizable Hilbert space…

Functional Analysis · Mathematics 2011-03-29 Fredy Vides

The dynamical spreading of quantum information through a many-body system, typically called scrambling, is a complex process that has proven to be essential to describe many properties of out-of-equilibrium quantum systems. Scrambling can,…

Quantum Physics · Physics 2024-03-22 Philip Daniel Blocher , Karthik Chinni , Sivaprasad Omanakuttan , Pablo M. Poggi

We implement the discrete-time quantum walk model using the continuous-time evolution of the Hamiltonian that includes both the shift and the coin generators. Based on the Trotter-Suzuki first-order approximation, we consider an…

Quantum Physics · Physics 2022-03-03 Jalil Khatibi Moqadam , Marcos Cesar de Oliveira

We summarize a recent study of discrete (integer-valued) Hamiltonian cellular automata (CA) showing that their dynamics can only be consistently defined, if it is linear in the same sense as unitary evolution described by the Schr\"odinger…

Quantum Physics · Physics 2014-10-13 Hans-Thomas Elze

Avila recently introduced a new method for the study of the discrete Schr\"odinger Operator with limit periodic potential. I adapt this method to the context of orthogonal polynomials in the unit circle with limit periodic Verblunsky…

Spectral Theory · Mathematics 2012-02-29 Darren C. Ong

The nonrelativistic Schroedinger equation for motion of a structureless particle in four-dimensional space-time entails a well-known expression for the conserved four-vector field of local probability density and current that are associated…

Quantum Physics · Physics 2009-11-10 G. E. Hahne

The dynamics of a tracer particle in a glassy matrix of obstacles displays slow complex transport as the free volume approaches a critical value and the void space falls apart. We investigate the emerging subdiffusive motion of the test…

Statistical Mechanics · Physics 2011-01-20 Thomas Franosch , Markus Spanner , Teresa Bauer , Gerd E. Schröder-Turk , Felix Höfling

The transport of excitation probabilities amongst weakly coupled subunits is investigated for a class of finite quantum systems. It is demonstrated that the dynamical behavior of the transported quantity depends on the considered length…

Statistical Mechanics · Physics 2007-10-09 Robin Steinigeweg , Heinz-Peter Breuer , Jochen Gemmer

In this work, we derive an exact hydrodynamical description for the coupled, charge and operator dynamics, in a quantum many-body system with U(1) symmetry. Using an emergent symmetry in the complex Brownian SYK model with charge…

Strongly Correlated Electrons · Physics 2023-05-12 Lakshya Agarwal , Subhayan Sahu , Shenglong Xu

We present an improved version of commutator methods for unitary operators under a weak regularity condition. Once applied to a unitary operator, the method typically leads to the absence of singularly continuous spectrum and to the local…

Mathematical Physics · Physics 2011-12-02 C. Fernandez , S. Richard , R. Tiedra de Aldecoa

We consider a simple modification of the 1D-Laplacian where non-mixed interface conditions occur at the boundaries of a finite interval. It has recently been shown that Schr\"odinger operators having this form allow a new approach to the…

Mathematical Physics · Physics 2015-06-11 Andrea Mantile

Formally symmetric differential operators on weighted Hardy-Hilbert spaces are analyzed, along with adjoint pairs of differential operators. Eigenvalue problems for such operators are rather special, but include many of the classical…

Classical Analysis and ODEs · Mathematics 2019-01-23 Robert Carlson

We propose diffusion-like equations with time and space fractional derivatives of the distributed order for the kinetic description of anomalous diffusion and relaxation phenomena, whose diffusion exponent varies with time and which,…

Statistical Mechanics · Physics 2009-11-07 A. V. Chechkin , R. Gorenflo , I. M. Sokolov

Operators in ergodic spin-chains are found to grow according to hydrodynamical equations of motion. The study of such operator spreading has aided our understanding of many-body quantum chaos in spin-chains. Here we initiate the study of…

Statistical Mechanics · Physics 2019-03-29 Sanjay Moudgalya , Trithep Devakul , C. W. von Keyserlingk , S. L. Sondhi