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We consider a one-dimensional Brownian motion of fixed duration $T$. Using a path-integral technique, we compute exactly the probability distribution of the difference $\tau=t_{\min}-t_{\max}$ between the time $t_{\min}$ of the global…

Statistical Mechanics · Physics 2020-05-13 Francesco Mori , Satya N. Majumdar , Gregory Schehr

Stochastic restarting is a strategy of starting anew. Incorporation of the resetting to the random walks can result in the decrease of the mean first passage time, due to the ability to limit unfavorably meandering, sub-optimal…

Statistical Mechanics · Physics 2023-11-08 Karol Capała , Bartłomiej Dybiec

In this paper we consider a stochastic process that may experience random reset events which bring suddenly the system to the starting value and analyze the relevant statistical magnitudes. We focus our attention on monotonous…

Mathematical Physics · Physics 2013-01-21 Miquel Montero , Javier Villarroel

The hitting time is the required minimum time for a Markov chain-based walk (classical or quantum) to reach a target state in the state space. We investigate the effect of the perturbation on the hitting time of a quantum walk. We obtain an…

Quantum Physics · Physics 2013-06-12 Chen-Fu Chiang , Guillermo Gomez

We investigate the role of a time and spin-dependent phase shift on the evolution of one-dimensional discrete-time quantum walks. By employing Floquet engineering, a time and spin-dependent phase shift ($\phi$) is imprinted onto the…

Quantum Physics · Physics 2021-10-04 Muhammad Sajid , Qurat ul Ain , Hanifa Qureshi , Tulva Tayyeba

We define the hitting (or absorbing) time for the case of continuous quantum walks by measuring the walk at random times, according to a Poisson process with measurement rate $\lambda$. From this definition we derive an explicit formula for…

Quantum Physics · Physics 2010-02-11 Martin Varbanov , Hari Krovi , Todd A. Brun

We study hitting times in simple random walks on graphs, which measure the time required to reach specific target vertices. Our main result establishes a sharp lower bound for the variance of hitting times. For a simple random walk on a…

Probability · Mathematics 2024-03-25 Rafael Chiclana , Yuval Peres

Restart is a common strategy observed in nature that accelerates first-passage processes and has been extensively studied using classical random walks. In the quantum regime, restart in continuous-time quantum walks (CTQWs) has been shown…

Quantum Physics · Physics 2025-04-22 Kunal Shukla , Riddhi Chatterjee , C. M. Chandrashekar

We propose a new model for a measurement of a characteristic of a microscopic quantum state by a large system that selects stochastically the different eigenstates with appropriate quantum weights. Unlike previous works which formulate a…

Quantum Physics · Physics 2009-01-24 Fariel Shafee

We aim to increase the ability of a of coupled phase oscillators to maintain the synchronization when the system is affected by stochastic disturbances. We model the disturbances by Gaussian noise and use the mean first hitting time when…

Adaptation and Self-Organizing Systems · Physics 2023-04-26 Xian Wu , Kaihua Xi , Aijie Cheng , Hai Xiang Lin , Jan H. van Schuppen

In one-dimensional random walks, the waiting time for each direction transitions is the same, even in the presence of bias, as a consequence of the microscopic-reversibility. We study the symmetry breaking of forward/ backward transition…

Statistical Mechanics · Physics 2020-10-28 Jaeoh Shin , Anatoly B. Kolomeisky

A second-order random walk on a graph or network is a random walk where transition probabilities depend not only on the present node but also on the previous one. A notable example is the non-backtracking random walk, where the walker is…

Probability · Mathematics 2021-12-28 Dario Fasino , Arianna Tonetto , Francesco Tudisco

Hitting times provide a fundamental measure of distance in random processes, quantifying the expected number of steps for a random walk starting at node $u$ to reach node $v$. They have broad applications across domains such as network…

Data Structures and Algorithms · Computer Science 2025-11-07 Themistoklis Haris , Fabian Spaeh , Spyros Dragazis , Charalampos Tsourakakis

Quantum walks are standard tools for searching graphs for marked vertices, and they often yield quadratic speedups over a classical random walk's hitting time. In some exceptional cases, however, the system only evolves by sign flips,…

Quantum Physics · Physics 2017-05-05 Thomas G. Wong , Raqueline A. M. Santos

Stochastic restart may drastically reduce the expected run time of a computer algorithm, expedite the completion of a complex search process, or increase the turnover rate of an enzymatic reaction. These diverse first-passage-time (FPT)…

Statistical Mechanics · Physics 2020-10-30 Shlomi Reuveni

Quantum random walks have been much studied recently, largely due to their highly nonclassical behavior. In this paper, we study one possible route to classical behavior for the discrete quantum random walk on the line: the use of multiple…

Quantum Physics · Physics 2009-11-07 Todd A. Brun , Hilary A. Carteret , Andris Ambainis

A random walk (or a Wiener process), possibly with drift, is observed in a noisy or delayed fashion. The problem considered in this paper is to estimate the first time \tau the random walk reaches a given level. Specifically, the p-moment…

Information Theory · Computer Science 2012-03-22 Marat V. Burnashev , Aslan Tchamkerten

In empirical studies of random walks, continuous trajectories of animals or individuals are usually sampled over a finite number of points in space and time. It is however unclear how this partial observation affects the measured…

Physics and Society · Physics 2018-03-13 Riccardo Gallotti , Rémi Louf , Jean-Marc Luck , Marc Barthelemy

Stochastic resetting -- the intermittent restart of random processes -- has profoundly reshaped first-passage theory, providing a mechanism to control and optimize completion times. While the influence of resetting on mean first-passage…

Probability · Mathematics 2026-03-27 Juan Antonio Vega Coso

We study a spin-1/2-particle moving on a one dimensional lattice subject to disorder induced by a random, space-dependent quantum coin. The discrete time evolution is given by a family of random unitary quantum walk operators, where the…

Quantum Physics · Physics 2015-05-27 Andre Ahlbrecht , Volkher B. Scholz , Albert H. Werner