English
Related papers

Related papers: Quantum Search on Computation Trees

200 papers

A recent breakthrough by Ambainis, Balodis, Iraids, Kokainis, Pr\=usis and Vihrovs (SODA'19) showed how to construct faster quantum algorithms for the Traveling Salesman Problem and a few other NP-hard problems by combining in a novel way…

Quantum Physics · Physics 2020-07-16 Masayuki Miyamoto , Masakazu Iwamura , Koichi Kise , François Le Gall

Quantum search is a quantum mechanical technique for searching N possibilities in only sqrt(N) steps. This paper gives a fresh perspective on the algorithm in terms of a resonance phenomenon which is implemented through classical coupled…

Quantum Physics · Physics 2007-05-23 Lov K. Grover , Anirvan Sengupta

We provide more sample-efficient versions of some basic routines in quantum data analysis, along with simpler proofs. Particularly, we give a quantum "Threshold Search" algorithm that requires only $O((\log^2 m)/\epsilon^2)$ samples of a…

Quantum Physics · Physics 2024-08-07 Costin Bădescu , Ryan O'Donnell

In this paper, we propose an explicit, non-strict representation of search trees in constraint-logic object-oriented programming. Our search tree representation includes both the non-deterministic and deterministic behaviour during…

Programming Languages · Computer Science 2020-09-23 Jan C. Dageförde , Finn Teegen

Ordered search is the task of finding an item in an ordered list using comparison queries. The best exact classical algorithm for this fundamental problem uses $\lceil \log_{2}{n}\rceil$ queries for a list of length $n$. Quantum computers…

Quantum Physics · Physics 2025-08-01 Joseph Carolan , Andrew M. Childs , Matt Kovacs-Deak , Luke Schaeffer

Let G=(V,E) be a finite graph, and f:V->N be any function. The Local Search problem consists in finding a local minimum of the function f on G, that is a vertex v such that f(v) is not larger than the value of f on the neighbors of v in G.…

Quantum Physics · Physics 2007-05-23 Yves F. Verhoeven

Let $G$ be an $n$-vertex graph with $m$ edges. When asked a subset $S$ of vertices, a cut query on $G$ returns the number of edges of $G$ that have exactly one endpoint in $S$. We show that there is a bounded-error quantum algorithm that…

Data Structures and Algorithms · Computer Science 2020-08-05 Troy Lee , Miklos Santha , Shengyu Zhang

We study quantum algorithms for several fundamental string problems, including Longest Common Substring, Lexicographically Minimal String Rotation, and Longest Square Substring. These problems have been widely studied in the stringology…

Data Structures and Algorithms · Computer Science 2021-10-22 Shyan Akmal , Ce Jin

The quantum search algorithm is a technique for searching N possibilities in only sqrt(N) steps. Although the algorithm itself is widely known, not so well known is the series of steps that first led to it, these are quite different from…

Quantum Physics · Physics 2009-11-07 Lov K. Grover

We show that it is possible to use a quantum walk to find a path from one marked vertex to another. In the specific case of $M$ stars connected in a chain, one can find the path from the first star to the last one in $O(M\sqrt{N})$ steps,…

Quantum Physics · Physics 2017-09-19 Daniel Reitzner , Mark Hillery , Daniel Koch

We propose a physical implementation of the quantum NAND tree evaluation algorithm. Our approach, based on continuous time quantum walks, uses the wave interference of a single electron in a heirarchical set of tunnel coupled quantum dots.…

Quantum Physics · Physics 2007-08-13 J. M. Taylor

Random walks describe diffusion processes, where movement at every time step is restricted to only the neighbouring locations. We construct a quantum random walk algorithm, based on discretisation of the Dirac evolution operator inspired by…

Quantum Physics · Physics 2015-03-13 Apoorva Patel , Md. Aminoor Rahaman

We present a framework wherein the trajectory optimization problem (or a problem involving calculus of variations) is formulated as a search problem in a discrete space. A distinctive feature of our work is the treatment of discretization…

Optimization and Control · Mathematics 2022-12-22 Alok Shukla , Prakash Vedula

This paper examines the performance of spatial search where the Grover diffusion operator is replaced by continuous-time quantum walks on a class of interdependent networks. We prove that for a set of optimal quantum walk times and marked…

Quantum Physics · Physics 2021-08-26 S. Marsh , J. B. Wang

Given a random function $f$ with domain $[2^n]$ and codomain $[2^m]$, with $m \geq n$, a collision of $f$ is a pair of distinct inputs with the same image. Collision finding is an ubiquitous problem in cryptanalysis, and it has been well…

Quantum Physics · Physics 2022-05-30 Xavier Bonnetain , André Chailloux , André Schrottenloher , Yixin Shen

We give a quantum algorithm for finding a marked element on the grid when there are multiple marked elements. Our algorithm uses quadratically fewer steps than a random walk on the grid, ignoring logarithmic factors. This is the first known…

Quantum Physics · Physics 2017-07-04 Peter Hoyer , Mojtaba Komeili

We prove that any exact quantum algorithm searching an ordered list of N elements requires more than \frac{1}{\pi}(\ln(N)-1) queries to the list. This improves upon the previously best known lower bound of {1/12}\log_2(N) - O(1). Our proof…

Quantum Physics · Physics 2007-05-23 Peter Hoyer , Jan Neerbek

Given an item and a list of values of size $N$. It is required to decide if such item exists in the list. Classical computer can search for the item in O(N). The best known quantum algorithm can do the job in $O(\sqrt{N})$. In this paper, a…

Quantum Physics · Physics 2008-11-27 Ahmed Younes

We focus on the problem of performing random walks efficiently in a distributed network. Given bandwidth constraints, the goal is to minimize the number of rounds required to obtain a random walk sample. We first present a fast sublinear…

Distributed, Parallel, and Cluster Computing · Computer Science 2010-03-03 Atish Das Sarma , Danupon Nanongkai , Gopal Pandurangan , Prasad Tetali

Test-time compute scaling has emerged as a new axis along which to improve model accuracy, where additional computation is used at inference time to allow the model to think longer for more challenging problems. One promising approach for…