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Related papers: Quantum searching amidst uncertainty

200 papers

We describe a quantum algorithm to prepare an arbitrary pure state of a register of a quantum computer with fidelity arbitrarily close to 1. Our algorithm is based on Grover's quantum search algorithm. For sequences of states with suitably…

Quantum Physics · Physics 2007-05-23 Andrei N. Soklakov , Ruediger Schack

Imagine a phone directory containing N names arranged in completely random order. In order to find someone's phone number with a 50% probability, any classical algorithm (whether deterministic or probabilistic) will need to look at a…

Quantum Physics · Physics 2008-02-03 Lov K. Grover

The Quantum Approximate Optimization Algorithm (QAOA) constitutes one of the often mentioned candidates expected to yield a quantum boost in the era of near-term quantum computing. In practice, quantum optimization will have to compete with…

Quantum Physics · Physics 2020-10-15 Charles Moussa , Henri Calandra , Vedran Dunjko

A quantum algorithm is a set of instructions for a quantum computer, however, unlike algorithms in classical computer science their results cannot be guaranteed. Quantum search algorithm can be described as the rotation of state vectors in…

Quantum Physics · Physics 2021-12-30 Bikramaditya Das , Kamal Gurnani , Bikash K. Behera , Prasanta K. Panigrahi

We present a number of results related to quantum algorithms with small error probability and quantum algorithms that are zero-error. First, we give a tight analysis of the trade-offs between the number of queries of quantum search…

Computational Complexity · Computer Science 2007-05-23 H. Buhrman , R. Cleve , R. de Wolf , Ch. Zalka

We study quantum algorithms for spatial search on finite dimensional grids. Patel et al. and Falk have proposed algorithms based on a quantum walk without a coin, with different operators applied at even and odd steps. Until now, such…

Quantum Physics · Physics 2015-10-14 Andris Ambainis , Renato Portugal , Nikolay Nahimov

It has recently been shown that starting with a classical query algorithm (decision tree) and a guessing algorithm that tries to predict the query answers, we can design a quantum algorithm with query complexity $O(\sqrt{GT})$ where $T$ is…

Quantum Physics · Physics 2022-10-18 Salman Beigi , Leila Taghavi , Artin Tajdini

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

The quantum SearchRank algorithm is a promising tool for a future quantum search engine based on PageRank quantization. However, this algorithm loses its functionality when the $N/M$ ratio between the network size $N$ and the number of…

Quantum Physics · Physics 2024-10-22 Sergio A. Ortega , Miguel A. Martin-Delgado

We study quantum algorithms working on classical probability distributions. We formulate four different models for accessing a classical probability distribution on a quantum computer, which are derived from previous work on the topic, and…

Quantum Physics · Physics 2019-04-05 Aleksandrs Belovs

Quantum algorithms can be analyzed in a query model to compute Boolean functions where input is given in a black box, but the aim is to compute function value for arbitrary input using as few queries as possible. In this paper we…

Quantum Physics · Physics 2012-03-24 Alina Dubrovska Vasilieva , Taisia Mischenko-Slatenkova

In this paper, we consider the partial database search problem where given a database on N items, we are required to determine the first k bits of an address x such that f(x)=1. We derive an algorithm and a lower bound for this problem in…

Quantum Physics · Physics 2007-05-23 Lov K. Grover , Jaikumar Radhakrishnan

Grover's algorithm is one of the pioneering demonstrations of the advantages of quantum computing over its classical counterpart, providing - at most - a quadratic speed-up over the classical solution for unstructured database search. The…

Grover's algorithm accelerates unstructured database search quadratically compared to classical algorithms. In the NISQ era, distributed quantum computing can decrease circuit depth and reduce noise. In this paper, an algorithm for…

Quantum Physics · Physics 2026-04-16 Huaijing Huang , Daowen Qiu , Ximing Hua , Xinyu Chen

We introduce a novel deterministic quantum search algorithm that provides a practical alternative to conventional probabilistic search approaches. Our scheme eliminates the inherent uncertainty of quantum search without relying on arbitrary…

Quantum Physics · Physics 2025-07-22 John Burke , Ciaran McGoldrick

We consider a database separated into blocks. Blocks containing target items are called target blocks. Blocks without target items are called non-target blocks. We consider a case, when each target block has the same number of target items.…

Quantum Physics · Physics 2007-06-06 Byung-Soo Choi , Vladimir Korepin

Quantum computing has evolved quickly in recent years and is showing significant benefits in a variety of fields, especially in the realm of cybersecurity. The combination of software used to locate the most frequent hashes and $n$-grams…

Quantum Physics · Physics 2022-05-09 Nicholas R. Allgood , Charles K. Nicholas

With the rapid development of quantum computers, quantum algorithms have been studied extensively. However, quantum algorithms tackling statistical problems are still lacking. In this paper, we propose a novel non-oracular quantum adaptive…

Methodology · Statistics 2021-07-20 Wenxuan Zhong , Yuan Ke , Ye Wang , Yongkai Chen , Jinyang Chen , Ping Ma

We initiate a systematic study of pseudo-deterministic quantum algorithms. These are quantum algorithms that, for any input, output a canonical solution with high probability. Focusing on the query complexity model, our main contributions…

Quantum Physics · Physics 2026-02-20 Hugo Aaronson , Tom Gur , Jiawei Li

We propose a probabilistic quantum algorithm that decides whether a monochrome picture matches a given template (or one out of a set of templates). As a major advantage to classical pattern recognition, the algorithm just requires a few…

Quantum Physics · Physics 2008-08-28 Gernot Schaller , Ralf Schützhold