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In this paper we study quantum algorithms for NP-complete problems whose best classical algorithm is an exponential time application of dynamic programming. We introduce the path in the hypercube problem that models many of these dynamic…

The Grover search algorithm performs an unstructured search of a marked item in a database quadratically faster than classical algorithms and is shown to be optimal. Here, we show that if the search space is divided into two blocks with the…

Quantum Physics · Physics 2023-12-12 Akankshya Dash , Biswaranjan Panda , Arun K Pati

One of the most important quantum algorithms ever discovered is Grover's algorithm for searching an unordered set. We give a new lower bound in the query model which proves that Grover's algorithm is exactly optimal. Similar to existing…

Quantum Physics · Physics 2022-02-01 Catalin Dohotaru , Peter Hoyer

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…

Quantum computing has noteworthy speedup over classical computing by taking advantage of quantum parallelism, i.e., the superposition of states. In particular, quantum search is widely used in various computationally hard problems. Grover's…

Quantum Physics · Physics 2021-03-29 Ji Liu , Huiyang Zhou

This paper presents an enhancement to Grover's search algorithm for instances where the number of items (or the size of the search problem) $N$ is not a power of 2. By employing an efficient algorithm for the preparation of uniform quantum…

Quantum Physics · Physics 2025-06-06 Alok Shukla , Prakash Vedula

Grover Search is currently one of the main quantum algorithms leading to hybrid quantum-classical methods that reduce the worst-case time complexity for some combinatorial optimization problems. Specifically, the combination of Quantum…

Quantum Physics · Physics 2024-08-13 Camille Grange , Michael Poss , Eric Bourreau , Vincent T'kindt , Olivier Ploton

The hybrid quantum-classical learning scheme provides a prominent way to achieve quantum advantages on near-term quantum devices. A concrete example towards this goal is the quantum neural network (QNN), which has been developed to…

Quantum Physics · Physics 2022-05-31 Yuxuan Du , Min-Hsiu Hsieh , Tongliang Liu , Dacheng Tao

Grover's algorithm achieves a quadratic speedup over classical algorithms, but it is considered necessary to know the value of $\lambda$ exactly [Phys. Rev. Lett. 95, 150501 (2005); Phys. Rev. Lett. 113, 210501 (2014)], where $\lambda$ is…

Quantum Physics · Physics 2018-12-12 Tan Li , Wan-Su Bao , He-Liang Huang , Feng-Guang Li , Xiang-Qun Fu , Shuo Zhang , Chu Guo , Yu-Tao Du , Xiang Wang , Jie Lin

Grover's search algorithm is one of the first quantum algorithms to exhibit a provable quantum advantage. It forms the backbone of numerous quantum applications and is widely used in benchmarking efforts. Here, we report…

Quantum Physics · Physics 2022-11-10 Bibek Pokharel , Daniel Lidar

Grover's algorithm is a quantum search algorithm that proceeds by repeated applications of the Grover operator and the Oracle until the state evolves to one of the target states. In the standard version of the algorithm, the Grover operator…

Quantum Physics · Physics 2018-03-14 Tim Byrnes , Gary Forster , Louis Tessler

Quantum search algorithms are considered in the context of protein sequence comparison in biocomputing. Given a sample protein sequence of length m (i.e m residues), the problem considered is to find an optimal match in a large database…

Quantum Physics · Physics 2009-11-06 Lloyd C. L. Hollenberg

Grover's quantum algorithm improves any classical search algorithm. We show how random Gaussian noise at each step of the algorithm can be modelled easily because of the exact recursion formulas available for computing the quantum amplitude…

Quantum Physics · Physics 2009-10-31 B. Pablo-Norman , M. Ruiz-Altaba

Quantum computation has attracted much attention since it was shown by Shor and Grover the possibility to implement quantum algorithms able to realize, respectively, factoring and searching in a faster way than any other known classical…

Quantum Physics · Physics 2007-05-23 Rubens Viana Ramos , Paulo Benicio de Sousa , David Sena Oliveira

Quantum algorithms can deliver asymptotic speedups over their classical counterparts. However, there are few cases where a substantial quantum speedup has been worked out in detail for reasonably-sized problems, when compared with the best…

Quantum Physics · Physics 2019-07-24 Earl Campbell , Ankur Khurana , Ashley Montanaro

Grover's algorithm, orginally conceived as a means of searching an unordered database, can also be used to extract solutions from the result sets generated by quantum computations. The Grover algorithm exploits the concept of an oracle…

Quantum Physics · Physics 2024-11-19 Fintan M. Bolton

Quantum computation, in particular Grover's algorithm, has aroused a great deal of interest since it allows for a quadratic speedup to be obtained in search procedures. Classical search procedures for an $N$ element database require at most…

Data Structures and Algorithms · Computer Science 2015-02-09 Luís Tarrataca , Andreas Wichert

The main approach to hybrid quantum-classical neural networks (QNN) is employing quantum computing to build a neural network (NN) that has quantum features, which is then optimized classically. Here, we propose a different strategy: to use…

Quantum Physics · Physics 2025-04-22 Stefan-Alexandru Jura , Mihai Udrescu

This paper shows that, if we could examine the entire history of a hidden variable, then we could efficiently solve problems that are believed to be intractable even for quantum computers. In particular, under any hidden-variable theory…

Quantum Physics · Physics 2007-05-23 Scott Aaronson

Quantum Computing offers an entirely new way of doing computation governed by the rules of quantum mechanics like Superposition and Entanglement. These rules allow us to do computation over all the possible states simultaneously. Hence,…

Quantum Physics · Physics 2021-07-08 Mohd. Hussain Mir , Harkirat Singh