Download or read book Quantum Walks and Search Algorithms written by Renato Portugal and published by Springer Science & Business Media. This book was released on 2013-02-16 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book addresses an interesting area of quantum computation called quantum walks, which play an important role in building quantum algorithms, in particular search algorithms. Quantum walks are the quantum analogue of classical random walks. It is known that quantum computers have great power for searching unsorted databases. This power extends to many kinds of searches, particularly to the problem of finding a specific location in a spatial layout, which can be modeled by a graph. The goal is to find a specific node knowing that the particle uses the edges to jump from one node to the next. This book is self-contained with main topics that include: Grover's algorithm, describing its geometrical interpretation and evolution by means of the spectral decomposition of the evolution operator Analytical solutions of quantum walks on important graphs like line, cycles, two-dimensional lattices, and hypercubes using Fourier transforms Quantum walks on generic graphs, describing methods to calculate the limiting distribution and mixing time Spatial search algorithms, with emphasis on the abstract search algorithm (the two-dimensional lattice is used as an example) Szedgedy's quantum-walk model and a natural definition of quantum hitting time (the complete graph is used as an example) The reader will benefit from the pedagogical aspects of the book, learning faster and with more ease than would be possible from the primary research literature. Exercises and references further deepen the reader's understanding, and guidelines for the use of computer programs to simulate the evolution of quantum walks are also provided.
Download or read book Quantum Walks and Search Algorithms written by Renato Portugal and published by Springer. This book was released on 2018-08-20 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: The revised edition of this book offers an extended overview of quantum walks and explains their role in building quantum algorithms, in particular search algorithms. Updated throughout, the book focuses on core topics including Grover's algorithm and the most important quantum walk models, such as the coined, continuous-time, and Szedgedy's quantum walk models. There is a new chapter describing the staggered quantum walk model. The chapter on spatial search algorithms has been rewritten to offer a more comprehensive approach and a new chapter describing the element distinctness algorithm has been added. There is a new appendix on graph theory highlighting the importance of graph theory to quantum walks. As before, the reader will benefit from the pedagogical elements of the book, which include exercises and references to deepen the reader's understanding, and guidelines for the use of computer programs to simulate the evolution of quantum walks. Review of the first edition: “The book is nicely written, the concepts are introduced naturally, and many meaningful connections between them are highlighted. The author proposes a series of exercises that help the reader get some working experience with the presented concepts, facilitating a better understanding. Each chapter ends with a discussion of further references, pointing the reader to major results on the topics presented in the respective chapter.” - Florin Manea, zbMATH.
Download or read book Quantum Walks and Search Algorithms written by and published by Springer. This book was released on 2013-02-19 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physical Implementation of Quantum Walks written by Kia Manouchehri and published by Springer Science & Business Media. This book was released on 2013-08-23 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Given the extensive application of random walks in virtually every science related discipline, we may be at the threshold of yet another problem solving paradigm with the advent of quantum walks. Over the past decade, quantum walks have been explored for their non-intuitive dynamics, which may hold the key to radically new quantum algorithms. This growing interest has been paralleled by a flurry of research into how one can implement quantum walks in laboratories. This book presents numerous proposals as well as actual experiments for such a physical realization, underpinned by a wide range of quantum, classical and hybrid technologies.
Download or read book Graph Theory Quantum Walk written by N.B. Singh and published by N.B. Singh. This book was released on with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Graph Theory: Quantum Walk" explores how quantum computing enhances our understanding and applications of graphs. From basic principles to advanced algorithms, the book shows how quantum mechanics revolutionizes computation in graph theory. Whether you're a student, researcher, or enthusiast, discover the exciting potential where quantum principles meet graph theory, offering new insights and computational strategies in this dynamic field.
Download or read book Query Complexity written by Mario Szegedy and published by World Scientific Publishing Company. This book was released on 2018-06-30 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantum Walks and Structured Searches on Free Groups and Networks written by Michael Ratner and published by . This book was released on 2017 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum walks have been utilized by many quantum algorithms which provide improved performance over their classical counterparts. Quantum search algorithms, the quantum analogues of spatial search algorithms, have been studied on a wide variety of structures. We study quantum walks and searches on the Cayley graphs of finitely-generated free groups. Return properties are analyzed via Green's functions, and quantum searches are examined. Additionally, the stopping times and success rates of quantum searches on random networks are experimentally estimated.
Download or read book Quantum Computing An Applied Approach written by Jack D. Hidary and published by Springer Nature. This book was released on 2021-09-29 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book integrates the foundations of quantum computing with a hands-on coding approach to this emerging field; it is the first to bring these elements together in an updated manner. This work is suitable for both academic coursework and corporate technical training. The second edition includes extensive updates and revisions, both to textual content and to the code. Sections have been added on quantum machine learning, quantum error correction, Dirac notation and more. This new edition benefits from the input of the many faculty, students, corporate engineering teams, and independent readers who have used the first edition. This volume comprises three books under one cover: Part I outlines the necessary foundations of quantum computing and quantum circuits. Part II walks through the canon of quantum computing algorithms and provides code on a range of quantum computing methods in current use. Part III covers the mathematical toolkit required to master quantum computing. Additional resources include a table of operators and circuit elements and a companion GitHub site providing code and updates. Jack D. Hidary is a research scientist in quantum computing and in AI at Alphabet X, formerly Google X.
Download or read book Quantum Walks for Computer Scientists written by Salvador Venegas-Andraca and published by Morgan & Claypool Publishers. This book was released on 2008-10-08 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum computation, one of the latest joint ventures between physics and the theory of computation, is a scientific field whose main goals include the development of hardware and algorithms based on the quantum mechanical properties of those physical systems used to implement such algorithms. Solving difficult tasks (for example, the Satisfiability Problem and other NP-complete problems) requires the development of sophisticated algorithms, many ofwhich employ stochastic processes as their mathematical basis. Discrete random walks are a popular choice among those stochastic processes. Inspired on the success of discrete random walks in algorithm development, quantum walks, an emerging field of quantum computation, is a generalization of random walks into the quantum mechanical world. The purpose of this lecture is to provide a concise yet comprehensive introduction to quantum walks. Table of Contents: Introduction / Quantum Mechanics / Theory of Computation / Classical Random Walks / Quantum Walks / Computer Science and Quantum Walks / Conclusions
Download or read book Quantum Algorithms for Searching Resampling and Hidden Shift Problems written by Māris Ozols and published by . This book was released on 2012 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is on quantum algorithms. It has three main themes: (1) quantum walk based search algorithms, (2) quantum rejection sampling, and (3) the Boolean function hidden shift problem. The first two parts deal with generic techniques for constructing quantum algorithms, and the last part is on quantum algorithms for a specific algebraic problem. In the first part of this thesis we show how certain types of random walk search algorithms can be transformed into quantum algorithms that search quadratically faster. More formally, given a random walk on a graph with an unknown set of marked vertices, we construct a quantum walk that finds a marked vertex in a number of steps that is quadratically smaller than the hitting time of the random walk. The main idea of our approach is to interpolate the random walk from one that does not stop when a marked vertex is found to one that stops. The quantum equivalent of this procedure drives the initial superposition over all vertices to a superposition over marked vertices. We present an adiabatic as well as a circuit version of our algorithm, and apply it to the spatial search problem on the 2D grid. In the second part we study a quantum version of the problem of resampling one probability distribution to another. More formally, given query access to a black box that produces a coherent superposition of unknown quantum states with given amplitudes, the problem is to prepare a coherent superposition of the same states with different specified amplitudes. Our main result is a tight characterization of the number of queries needed for this transformation. By utilizing the symmetries of the problem, we prove a lower bound using a hybrid argument and semidefinite programming. For the matching upper bound we construct a quantum algorithm that generalizes the rejection sampling method first formalized by von~Neumann in~1951. We describe quantum algorithms for the linear equations problem and quantum Metropolis sampling as applications of quantum rejection sampling. In the third part we consider a hidden shift problem for Boolean functions: given oracle access to f(x+s), where f(x) is a known Boolean function, determine the hidden shift s. We construct quantum algorithms for this problem using the "pretty good measurement" and quantum rejection sampling. Both algorithms use the Fourier transform and their complexity can be expressed in terms of the Fourier spectrum of f (in particular, in the second case it relates to "water-filling" of the spectrum). We also construct algorithms for variations of this problem where the task is to verify a given shift or extract only a single bit of information about it.
Download or read book A Primer on Quantum Computing written by Franklin de Lima Marquezino and published by Springer. This book was released on 2019-06-25 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is about quantum computing and quantum algorithms. The book starts with a chapter introducing the basic rules of quantum mechanics and how they can be used to build quantum circuits and perform computations. Further, Grover's algorithm is presented for unstructured search discussing its consequences and applications. Next, important techniques are discussed such as Quantum Fourier Transform and quantum phase estimation. Finally, Shor's algorithm for integer factorization is explained. At last, quantum walks are explained in detail covering both the discrete and continuous time models,and applications of this techniques are described for the design and analyses of quantum algorithms.
Download or read book Frameworks for Quantum Algorithms written by Stacey Jeffery and published by . This book was released on 2014 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to the difficulty of constructing new quantum algorithms, frameworks that facilitate this construction are of great importance in quantum computing. These frameworks reduce the problem of coming up with a quantum algorithm to that of constructing some combinatorial object that is often much simpler to reason about. The implementation and analysis of an algorithm for the specified problem follow from the properties of this object. A number of such frameworks have been extremely successful in leading to the development of numerous quantum algorithms for a variety of problems. In this thesis, we build on two of these frameworks, the quantum walk search framework, and the span program framework, extending their algorithmic potential. The quantum walk search framework gives a generic quantum analogue to a specific type of classical algorithm based on random walks. If one can construct a classical algorithm of this form, a corresponding quantum algorithm with better complexity immediately follows. In this framework, a generic algorithm is constructed from several subroutines for which implementations must be given for each application. One of these subroutines, a checking subroutine, is run many times throughout the algorithm. This subroutine may be implemented by any quantum algorithm that satisfies the required functionality, including another quantum walk algorithm. By making a slight modification to the quantum walk framework, we can show how to nest a quantum walk algorithm in the checking subroutine of another quantum walk algorithm in a way that gives better complexity than the naive nesting. This modification allows us to reproduce a number of upper bounds previously obtained in another framework, the learning graph framework, including upper bounds for triangle finding, and more generally, subgraph finding for constant-sized subgraphs. Porting these upper bounds over to the setting of quantum walks is desirable because the algorithms achieved in the quantum walk search framework are much more explicit than those of the learning graph framework, making them easier to work with, modify, and build on, as needed. Our efficient nested checking idea has already been used to come up with new quantum algorithms for finding sub-hypergraphs. Another subroutine that is called repeatedly by the generic quantum walk search algorithm is the update subroutine. It was not clear how to use a quantum walk algorithm to perform this step, but by making another slight modification to the quantum walk search framework, we are able to show how to nest a quantum walk in the update step of another quantum walk in an efficient way. Our technique for doing this is a special case of a technique that allows the update to be implemented with garbage -- i.e., some unwanted data in an auxiliary register, entangled with the desired state. This technique may have other applications. Using the nested update technique, we are able to improve the best known upper bounds on the time complexity of $k$-distinctness. Previously the best known upper bound on the time complexity was $n^{k/(k+1)}$, due to Ambainis. Belovs had recently improved the query complexity of $k$-distinctness to $o(n^{3/4})$ for all $k$, but since this upper bound was obtained in a framework called span programs, which only gives upper bounds on quantum query complexity, there was no known time efficient implementation of his $k$-distinctness algorithm. We use ideas from his construction and our nested update technique to get a quantum time upper bound for $3$-distinctness of $n^{5/7}$, matching his quantum query upper bound. We can generalize our algorithm get a time upper bound of $n^{(k-1)/k}$ for any $k>3$, slightly improving on the best previous upper bound. Another framework, the span program framework, is known to be equivalent to quantum query complexity, in the sense that for any Boolean decision problem, there exists a span program construction that yields a tight upper bound on its quantum query complexity. We explore several variations of this framework. First, we slightly modify the definition of a span program so that we can show that for \emph{any} (not necessarily Boolean) decision problem, there is a span program construction that yields a tight upper bound on its quantum query complexity. Previously this was only known up to logarithmic factors. We also explore several approximate versions of span programs, and show them to be equivalent. Finally, we explore the structure of span program witnesses, and use this structure to present an algorithm for evaluating span programs that is straightforward and intuitive. We also show how to evaluate approximate span programs, opening the possibility for the construction of new upper bounds using approximate span programs.
Download or read book Quantum Image Processing written by Fei Yan and published by Springer Nature. This book was released on 2020-01-03 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive introduction to quantum image processing, which focuses on extending conventional image processing tasks to the quantum computing frameworks. It summarizes the available quantum image representations and their operations, reviews the possible quantum image applications and their implementation, and discusses the open questions and future development trends. It offers a valuable reference resource for graduate students and researchers interested in this emerging interdisciplinary field.
Download or read book Superconducting Devices in Quantum Optics written by Robert Hadfield and published by Springer. This book was released on 2016-02-29 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the basics and applications of superconducting devices in quantum optics. Over the past decade, superconducting devices have risen to prominence in the arena of quantum optics and quantum information processing. Superconducting detectors provide unparalleled performance for the detection of infrared photons in quantum cryptography, enable fundamental advances in quantum optics, and provide a direct route to on-chip optical quantum information processing. Superconducting circuits based on Josephson junctions provide a blueprint for scalable quantum information processing as well as opening up a new regime for quantum optics at microwave wavelengths. The new field of quantum acoustics allows the state of a superconducting qubit to be transmitted as a phonon excitation. This volume, edited by two leading researchers, provides a timely compilation of contributions from top groups worldwide across this dynamic field, anticipating future advances in this domain.
Download or read book Discrete Quantum Walks on Graphs and Digraphs written by Chris Godsil and published by Cambridge University Press. This book was released on 2023-01-12 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Discrete quantum walks are quantum analogues of classical random walks. They are an important tool in quantum computing and a number of algorithms can be viewed as discrete quantum walks, in particular Grover's search algorithm. These walks are constructed on an underlying graph, and so there is a relation between properties of walks and properties of the graph. This book studies the mathematical problems that arise from this connection, and the different classes of walks that arise. Written at a level suitable for graduate students in mathematics, the only prerequisites are linear algebra and basic graph theory; no prior knowledge of physics is required. The text serves as an introduction to this important and rapidly developing area for mathematicians and as a detailed reference for computer scientists and physicists working on quantum information theory.
Download or read book Quantum Data Structures Fundamentals written by N.B. Singh and published by N.B. Singh. This book was released on with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Quantum Data Structures Fundamentals" is a beginner-friendly exploration of the essential concepts underpinning quantum computing. Written for readers with non-mathematical backgrounds and absolute beginners, this book delves into the fundamental principles of quantum data structures, offering clear explanations and intuitive insights. From understanding the basics of qubits and quantum gates to exploring advanced topics such as quantum cryptography and quantum simulation, each chapter provides a comprehensive overview of key concepts in a reader-friendly manner. Through accessible language and practical examples, this book serves as an introductory guide to the fascinating world of quantum computing, empowering readers to grasp foundational concepts and lay the groundwork for further exploration in this rapidly evolving field.
Download or read book Some Limits on Quantum Walks on the Hypercubic and Decoherence of Grover s Search Algorithm written by Mussa Kahssay Abdulkadir and published by . This book was released on 2006 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
