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Related papers: Quantum random walks and their convergence

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Quantum walks are quantum counterparts of Markov chains. In this article, we give a brief overview of quantum walks, with emphasis on their algorithmic applications.

Quantum Physics · Physics 2008-05-12 Andris Ambainis

It is not currently known if quantum Turing machines can efficiently simulate probabilistic computations in the space-bounded case. In this paper we show that space-bounded quantum Turing machines can efficiently simulate a limited class of…

Computational Complexity · Computer Science 2007-05-23 John Watrous

We prove a quenched functional central limit theorem for a one-dimensional random walk driven by a simple symmetric exclusion process. This model can be viewed as a special case of the random walk in a balanced random environment, for which…

Probability · Mathematics 2021-07-20 Otávio Menezes , Jonathon Peterson , Yongjia Xie

We study the discrete quantum groups $\Gamma$ whose group algebra has an inner faithful representation of type $\pi:C^*(\Gamma)\to M_K(\mathbb C)$. Such a representation can be thought of as coming from an embedding $\Gamma\subset U_K$. Our…

Operator Algebras · Mathematics 2015-12-14 Teodor Banica , Julien Bichon

Although quantum walks exhibit peculiar properties that distinguish them from random walks, classical behavior can be recovered in the asymptotic limit by destroying the coherence of the pure state associated to the quantum system. Here I…

Quantum Physics · Physics 2016-06-16 Miquel Montero

This is a preprint of Chapter 2 in the following work: Marta Lewicka, A Course on Tug-of-War Games with Random Noise, 2020, Springer, reproduced with permission of Springer Nature Switzerland AG. We present the basic relation between the…

Analysis of PDEs · Mathematics 2020-07-24 Marta Lewicka

We study the evolution of a random walker on a conservative dynamic random environment composed of independent particles performing simple symmetric random walks, generalizing results of [16] to higher dimensions and more general transition…

Quantum random walks on graphs have been shown to display many interesting properties, including exponentially fast hitting times when compared with their classical counterparts. However, it is still unclear how to use these novel…

Quantum Physics · Physics 2009-11-07 Neil Shenvi , Julia Kempe , K. Birgitta Whaley

This manuscript gathers and subsumes a long series of works on using QW to simulate transport phenomena. Quantum Walks (QWs) consist of single and isolated quantum systems, evolving in discrete or continuous time steps according to a…

Quantum Physics · Physics 2021-12-23 Giuseppe Di Molfetta

The continuous limit of one dimensional discrete-time quantum walks with time- and space-dependent coefficients is investigated. A given quantum walk does not generally admit a continuous limit but some families (1-jets) of quantum walks…

Mathematical Physics · Physics 2017-04-25 Giuseppe Di Molfetta , Fabrice Debbasch

We consider the effect of different unitary noise mechanisms on the evolution of a quantum walk (QW) on a linear chain with a generic coin operation: (i) bit-flip channel noise, restricted to the coin subspace of the QW, and (ii)…

Quantum Physics · Physics 2007-11-27 G. Abal , R. Donangelo , F. Severo , R. Siri

Consider a one dimensional simple random walk $X=(X_n)_{n\geq0}$. We form a new simple symmetric random walk $Y=(Y_n)_{n\geq0}$ by taking sums of products of the increments of $X$ and study the two-dimensional walk…

Probability · Mathematics 2015-08-18 Andrea Collevecchio , Kais Hamza , Meng Shi

It is well known that many real world networks have the power-law degree distribution (scale-free property). However there are no rigorous results for continuous-time quantum walks on such realistic graphs. In this paper, we analyze…

Quantum Physics · Physics 2010-11-12 Yusuke Ide , Norio Konno

In all existing quantum walk models, the assumption about a pre-existing fixed background causal structure is always made and has been taken for granted. Nevertheless, in this work we will get rid of this tacit assumption especially by…

Quantum Physics · Physics 2022-02-15 Yuanbo Chen , Yoshihiko Hasegawa

The subject of this paper is a kind of dynamical systems called quantum walks. We study one-dimensional homogeneous analytic quantum walks U. We explain how to identify the space of all the uniform intertwining operators between these…

Mathematical Physics · Physics 2019-02-08 Hiroki Sako

In this work we seek to generalize the connection between traversable wormholes and quantum channels. We do this via a connection between traversable wormholes and graph geometries on which we can perform quantum random walks for signal…

High Energy Physics - Theory · Physics 2019-06-06 Ning Bao , Vincent P. Su , Mykhaylo Usatyuk

Quantum walks are versatile simulators of topological phases and phase transitions as observed in condensed matter physics. Here, we utilize a step dependent coin in quantum walks and investigate what topological phases we can simulate with…

Quantum Physics · Physics 2019-12-16 S. Panahiyan , S. Fritzsche

In this expository note, we discuss spatially inhomogeneous quantum walks in one dimension and describe a genre of mathematical methods that enables one to translate information about the time-independent eigenvalue equation for the unitary…

Spectral Theory · Mathematics 2017-04-25 Jake Fillman

Quantum walks have by now been realized in a large variety of different physical settings. In some of these, particularly with trapped ions, the walk is implemented in phase space, where the corresponding position states are not orthogonal.…

Quantum Physics · Physics 2014-04-02 R. Matjeschk , A. Ahlbrecht , M. Enderlein , Ch. Cedzich , A. H. Werner , M. Keyl , T. Schaetz , R. F. Werner

Using quantum parallelism on random walks as original seed, we introduce new quantum stochastic processes, the open quantum Brownian motions. They describe the behaviors of quantum walkers -- with internal degrees of freedom which serve as…

Mathematical Physics · Physics 2015-06-18 Michel Bauer , Denis Bernard , Antoine Tilloy