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Related papers: Hitting Time of Quantum Walks with Perturbation

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We study the computation of lower and upper probabilities of hitting a target set of states for imprecise Markov chains, where transition uncertainty is modelled by a convex set of transition matrices. In the precise case, hitting…

Probability · Mathematics 2026-03-18 Marco Sangalli , Erik Quaeghebeur , Thomas Krak

In this work we study quantum algorithms for Hopcroft's problem which is a fundamental problem in computational geometry. Given $n$ points and $n$ lines in the plane, the task is to determine whether there is a point-line incidence. The…

Quantum Physics · Physics 2024-05-03 Vladimirs Andrejevs , Aleksandrs Belovs , Jevgēnijs Vihrovs

Most approximation algorithms for #P-complete problems (e.g., evaluating the permanent of a matrix or the volume of a polytope) work by reduction to the problem of approximate sampling from a distribution $\pi$ over a large set $\S$. This…

Quantum Physics · Physics 2011-11-09 Peter C. Richter

Quantum walks, both discrete (coined) and continuous time, form the basis of several quantum algorithms and have been used to model processes such as transport in spin chains and quantum chemistry. The enhanced spreading and mixing…

Quantum Physics · Physics 2010-12-10 Godfrey Leung , Paul Knott , Joe Bailey , Viv Kendon

Discrete time quantum walks (DTQWs) are nontrivial generalizations of random walks with a broad scope of applications. In particular, they can be used as computational primitives, and they are suitable tools for simulating other quantum…

Quantum Physics · Physics 2015-02-13 Bálint Kollár , Tamás Kiss , Igor Jex

In this paper we are concerned with hitting times of a family of density-dependent Markov chains. A moderate deviation principle of the hitting time is given. The proof of the main theorem relies heavily on moderate deviations of…

Probability · Mathematics 2022-06-15 Yuheng He , Xiaofeng Xue

We introduce a new tool for quantum algorithms called quantum fast-forwarding (QFF). The tool uses quantum walks as a means to quadratically fast-forward a reversible Markov chain. More specifically, with $P$ the Markov chain transition…

Quantum Physics · Physics 2019-01-24 Simon Apers , Alain Sarlette

Quantum walks have wide applications in quantum information, such as universal quantum computation, so it is important to explore properties of quantum walks thoroughly. We propose a novel method to implement discrete-time quantum walks…

Quantum Physics · Physics 2022-06-09 Qi-Ping Su , Shi-Chao Wang , Yan Chi , Yong-Nan Sun , Li Yu , Zhe Sun , Franco Nori , Chui-Ping Yang

In this article we continue the study of the quenched distributions of transient, one-dimensional random walks in a random environment. In a previous article we showed that while the quenched distributions of the hitting times do not…

Probability · Mathematics 2016-06-14 Jonathon Peterson , Gennady Samorodnitsky

Motivated by applications in telecommunications, computer scienceand physics, we consider a discrete-time Markov process withrestart. At each step the process eitherwith a positive probability restarts from a given distribution, orwith the…

Performance · Computer Science 2017-03-13 Konstantin Avrachenkov , Alexey Piunovskiy , Yi Zhang

Quantum walks are well-known for their ballistic dispersion, traveling $\Theta(t)$ away in $t$ steps, which is quadratically faster than a classical random walk's diffusive spreading. In physical implementations of the walk, however, the…

Quantum Physics · Physics 2016-01-25 Thomas G. Wong

The quantum-walk-based spatial search problem aims to find a marked vertex using a quantum walk on a graph with marked vertices. We describe a framework for determining the computational complexity of spatial search by continuous-time…

Quantum Physics · Physics 2024-12-25 Pedro H. G. Lugão , Renato Portugal , Mohamed Sabri , Hajime Tanaka

We present a novel algorithm to solve a non-linear system of equations, whose solution can be interpreted as a tight lower bound on the vector of expected hitting times of a Markov chain whose transition probabilities are only partially…

Probability · Mathematics 2022-03-30 Thomas Krak

We study the first hitting time statistics between a one-dimensional run-and-tumble particle and a target site that switches intermittently between visible and invisible phases. The two-state dynamics of the target is independent of the…

Statistical Mechanics · Physics 2021-05-05 Gabriel Mercado-Vásquez , Denis Boyer

We present an introduction to coined quantum walks on regular graphs, which have been developed in the past few years as an alternative to quantum Fourier transforms for underpinning algorithms for quantum computation. We then describe our…

Quantum Physics · Physics 2018-03-28 Viv Kendon , Ben Tregenna

Several inequalities are proved for the mixing time of discrete-time quantum walks on finite graphs. The mixing time is defined differently than in Aharonov, Ambainis, Kempe and Vazirani (2001) and it is found that for particular examples…

Probability · Mathematics 2010-07-23 Vladislav Kargin

Mixing properties of discrete-time quantum walks on two-dimensional grids with torus-like boundary conditions are analyzed, focusing on their connection to the complexity of the corresponding abstract search algorithm. In particular, an…

Quantum Physics · Physics 2012-05-18 F. L. Marquezino , R. Portugal , G. Abal

This work examines the time complexity of quantum search algorithms on combinatorial $t$-designs with multiple marked elements using the continuous-time quantum walk. Through a detailed exploration of $t$-designs and their incidence…

Quantum Physics · Physics 2025-04-08 Pedro H. G. Lugão , Renato Portugal

We define the hitting time for a Markov decision process (MDP). We do not use the hitting time of the Markov process induced by the MDP because the induced chain may not have a stationary distribution. Even it has a stationary distribution,…

Machine Learning · Computer Science 2022-05-12 Ruichao Jiang , Javad Tavakoli , Yiqinag Zhao

We derive the continuous-time limit of discrete quantum walks with topological phases. We show the existence of a continuous-time limit that preserves their topological phases. We consider both simple-step and split-step walks, and derive…

Quantum Physics · Physics 2016-11-23 Radhakrishnan Balu , Daniel Castillo , George Siopsis , Christian Weedbrook