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The quantum walk was originally proposed as a quantum mechanical analogue of the classical random walk, and has since become a powerful tool in quantum information science. In this paper, we show that discrete time quantum walks provide a…

Mesoscale and Nanoscale Physics · Physics 2010-09-30 Takuya Kitagawa , Mark S. Rudner , Erez Berg , Eugene Demler

Lazy quantum walks were presented by Andrew M. Childs to prove that the continuous-time quantum walk is a limit of the discrete-time quantum walk [Commun.Math.Phys.294,581-603(2010)]. In this paper, we discuss properties of lazy quantum…

Quantum Physics · Physics 2015-09-01 Dan Li , Michael Mc Gettrick , Wei-Wei Zhang , Ke-Jia Zhang

Quantum walks have emerged as an interesting alternative to the usual circuit model for quantum computing. While still universal for quantum computing, the quantum walk model has very different physical requirements, which lends itself more…

Quantum Physics · Physics 2015-05-19 Peter P. Rohde , Andreas Schreiber , Martin Stefanak , Igor Jex , Christine Silberhorn

We study a random walk in random environment on the non-negative integers. The random environment is not homogeneous in law, but is a mixture of two kinds of site, one in asymptotically vanishing proportion. The two kinds of site are (i)…

Probability · Mathematics 2014-04-28 Ostap Hryniv , Mikhail V. Menshikov , Andrew R. Wade

We treat three types of measures of the quantum walk (QW) with the spatial perturbation at the origin, which was introduced by [1]: time averaged limit measure, weak limit measure, and stationary measure. From the first two measures, we see…

Quantum Physics · Physics 2013-06-12 Norio Konno , Tomasz Luczak , Etsuo Segawa

Discrete-time quantum walks (DTQWs) in random artificial electric and gravitational fields are studied analytically and numerically. The analytical computations are carried by a new method which allows a direct exact analytical…

Quantum Physics · Physics 2017-04-25 G. Di Molfetta , F. Debbasch

We study space-time fluctuations around a characteristic line for a one-dimensional interacting system known as the random average process. The state of this system is a real-valued function on the integers. New values of the function are…

Probability · Mathematics 2007-09-12 Marton Balazs , Firas Rassoul-Agha , Timo Seppalainen

Some physical effects of time averaged quantum electric field fluctuations are discussed. The one loop radiative correction to potential scattering are approximately derived from simple arguments which invoke vacuum electric field…

High Energy Physics - Theory · Physics 2015-06-10 Haiyun Huang , L. H. Ford

Asymptotic dynamics of a Hadamard walk of two non-interacting quantum particles on a dynamically percolated finite line or a circle is investigated. We construct a basis of the attractor space of the corresponding random-unitary dynamics…

Quantum Physics · Physics 2024-02-16 M. Paryzkova , M. Stefanak , J. Novotny , B. Kollar , T. Kiss

The origin of non-classicality in physical systems and its connection to distinctly quantum features such as entanglement and coherence is a central question in quantum physics. This work analyses this question theoretically and…

We consider a random walk in random environment with random holding times, that is, the random walk jumping to one of its nearest neighbors with some transition probability after a random holding time. Both the transition probabilities and…

Probability · Mathematics 2014-12-30 Ryoki Fukushima , Naoki Kubota

Quantum walks are known to propagate quadratically faster than their classical counterparts and are used to model dynamics in various quantum systems. The spread of the quantum walk in position space shows anomalous diffusion behavior. By…

Quantum Physics · Physics 2022-05-24 Abhaya S. Hegde , C. M. Chandrashekar

Two fundamental theorems by Spitzer/Erickson and Kesten/Maller on the fluctuation type (positive divergence, negative divergence or oscillation) of a real-valued random walk $(S_{n})_{n\ge 0}$ with iid increments $X_{1},X_{2},\ldots$ and…

Probability · Mathematics 2017-06-13 Gerold Alsmeyer , Fabian Buckmann

There are presently two models for quantum walks on graphs. The "coined" walk uses discrete time steps, and contains, besides the particle making the walk, a second quantum system, the coin, that determines the direction in which the…

Quantum Physics · Physics 2009-11-10 Mark Hillery , Janos Bergou , Edgar Feldman

This tutorial article showcases the many varieties and uses of quantum walks. Discrete time quantum walks are introduced as counterparts of classical random walks. The emphasis is on the connections and differences between the two types of…

Quantum Physics · Physics 2013-05-16 Daniel Reitzner , Daniel Nagaj , Vladimir Buzek

This paper is concerned with two questions in the decoherent histories approach to quantum mechanics: the emergence of approximate classical predictability, and the fluctuations about it necessitated by the uncertainty principle. We…

General Relativity and Quantum Cosmology · Physics 2009-10-22 J. J. Halliwell

Discrete quantum walks are periodically driven systems with discrete time evolution. In contrast to ordinary Floquet systems, no microscopic Hamiltonian exists, and the one-period time evolution is given directly by a series of unitary…

Mesoscale and Nanoscale Physics · Physics 2025-01-10 Ken Mochizuki , Takumi Bessho , Masatoshi Sato , Hideaki Obuse

Basic peculiarities of market price fluctuations are known to be well described by a recently developed random walk model in a temporally deforming quadric potential force whose center is given by a moving average of past price traces…

Statistical Finance · Quantitative Finance 2013-05-29 Kota Watanabe , Hideki Takayasu , Misako Takayasu

In the framework of the Lindblad theory for open quantum systems we determine the degree of quantum decoherence and classical correlations of a harmonic oscillator interacting with a thermal bath. The transition from quantum to classical…

Quantum Physics · Physics 2009-11-13 A. Isar , W. Scheid

This article traces the development of fluctuation theory and its deep connection to irreversibility, from equilibrium to near-equilibrium, and finally to far-from-equilibrium systems. Classical fluctuation theorems, which capture the…

Quantum Physics · Physics 2025-12-30 Sounak Bandyopadhyay , Arnab Ghosh