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Adiabatic quantum optimization is a procedure to solve a vast class of optimization problems by slowly changing the Hamiltonian of a quantum system. The evolution time necessary for the algorithm to be successful scales inversely with the…

Quantum Physics · Physics 2015-12-16 Salvatore Mandrà , Gian Giacomo Guerreschi , Alán Aspuru-Guzik

We present quantum algorithms for routing concentration assignments on full capacity fat-and-slim concentrators, bounded fat-and-slim concentrators, and regular fat-and-slim concentrators. Classically, the concentration assignment takes…

Quantum Physics · Physics 2021-03-19 Cem M. Unsal , A. Yavuz Oruc

Grover's algorithm for quantum searching is generalized to deal with arbitrary initial complex amplitude distributions. First order linear difference equations are found for the time evolution of the amplitudes of the marked and unmarked…

Quantum Physics · Physics 2016-09-08 Eli Biham , Ofer Biham , David Biron , Markus Grassl , Daniel A. Lidar

We prove that it is impossible to built a universal quantum machine that produces reflections about an unknown state. We then point out a connection between this result and the optimality of Grover's search algorithm: if such reflection…

Quantum Physics · Physics 2011-05-23 Karthikeyan S. Kumar , G. S. Paraoanu

Finding the shortest vector in a lattice is a problem that is believed to be hard both for classical and quantum computers. Many major post-quantum secure cryptosystems base their security on the hardness of the Shortest Vector Problem…

Quantum Physics · Physics 2025-03-06 Milos Prokop , Petros Wallden , David Joseph

This paper presents a complete algorithmic study of the decision Boolean Satisfiability Problem under the classical computation and quantum computation theories. The paper depicts deterministic and probabilistic algorithms, propositions of…

Computational Complexity · Computer Science 2016-02-22 Carlos Barrón-Romero

This work considers a generalization of Grover's search problem, viz., to find any one element in a set of acceptable choices which constitute a fraction f of the total number of choices in an unsorted data base. An infinite family of…

Quantum Physics · Physics 2009-11-07 Chia-Ren Hu

NP-hard problems are not believed to be exactly solvable through general polynomial time algorithms. Hybrid quantum-classical algorithms to address such combinatorial problems have been of great interest in the past few years. Such…

Quantum Physics · Physics 2024-01-15 Yagnik Chatterjee , Eric Bourreau , Marko J. Rančić

Quantum algorithms are conventionally formulated for implementation on a single system of qubits amenable to projective measurements. However, in expectation value quantum computation, such as nuclear magnetic resonance realizations, the…

Quantum Physics · Physics 2007-05-23 David Collins

We describe an implementation of Grover's fixed-point quantum search algorithm on a nuclear magnetic resonance (NMR) quantum computer, searching for either one or two matching items in an unsorted database of four items. In this new…

Quantum Physics · Physics 2007-05-23 Li Xiao , Jonathan A. Jones

The improved quantum scheduling algorithm proposed by Grover has been generalized using the generalized quantum search algorithm, in which a unitary operator replaces the Walsh-Hadamard transform, and $\pi/2$ phase rotations replace the…

Quantum Physics · Physics 2007-05-23 Jingfu Zhang , Zhiheng Lu , Zhiwei Deng , Hui Wang

Exploiting the similarity between adiabatic quantum algorithms and quantum phase transitions, we argue that second-order transitions -- typically associated with broken or restored symmetries -- should be advantageous in comparison to…

Quantum Physics · Physics 2010-01-07 Gernot Schaller , Ralf Schützhold

Grover's database search algorithm, although discovered in the context of quantum computation, can be implemented using any system that allows superposition of states. A physical realization of this algorithm is described using coupled…

Quantum Physics · Physics 2007-06-13 Apoorva Patel

In the recent years, we have seen that Grover search algorithm (Proceedings, 28th annual ACM symposium on the theory of computing, pp. 212-219, 1996) by using quantum parallelism has revolutionized the field of solving huge class of NP…

Quantum Physics · Physics 2017-05-23 Indranil Chakrabarty , Shahzor Khan , Vanshdeep Singh

Conditions on sure-success decidability of weights of Boolean functions are presented for a given number of generalized Grover iterations. It is shown that the decidability problem reduces to a system of algebraic equations of a single…

Quantum Physics · Physics 2013-01-21 K. Uyanik , S. Turgut

We deal with a problem of finding maximum of a function from the Holder class on a quantum computer. We show matching lower and upper bounds on the complexity of this problem. We prove upper bounds by constructing an algorithm that uses the…

Quantum Physics · Physics 2007-05-23 Maciej Gocwin

The closest pair problem is a fundamental problem of computational geometry: given a set of $n$ points in a $d$-dimensional space, find a pair with the smallest distance. A classical algorithm taught in introductory courses solves this…

Quantum Physics · Physics 2020-08-07 Scott Aaronson , Nai-Hui Chia , Han-Hsuan Lin , Chunhao Wang , Ruizhe Zhang

Grover's algorithm has achieved great success. But quantum search algorithms still are not complete algorithms because of Grover's Oracle. We concerned on this problem and present a new quantum search algorithm in adiabatic model without…

Quantum Physics · Physics 2009-09-29 Nanyang Xu , Jin Zhu , Xinhua Peng , Xianyi Zhou , Jiangfeng Du

The hidden subgroup problem~(HSP) is one of the most important problems in quantum computation. Many problems for which quantum algorithm achieves exponential speedup over its classical counterparts can be reduced to the Abelian HSP.…

Quantum Physics · Physics 2023-05-05 Hefeng Wang

In the continuum limit (large number of qubits), adiabatic quantum algorithms display a remarkable similarity to sweeps through quantum phase transitions. We find that transitions of second or higher order are advantageous in comparison to…

Quantum Physics · Physics 2015-06-26 Ralf Schützhold , Gernot Schaller