Quantum Computing

A brief introduction to quantum computing has recently appeared as a preprint on arxiv. Here are the details:

arXiv.org > quant-ph > arXiv:0712.1098

Quantum Computations: Fundamentals And Algorithms
Authors: Steven Duplij (Kharkov National University), Illia Shapoval (NSC Kharkov Institute of Physics and Technology)
(Submitted on 7 Dec 2007)

Abstract: Basic concepts of quantum theory of information, principles of quantum calculations and the possibility of creation on this basis unique on calculation power and functioning principle device, named quantum computer, are briefly reviewed. The main blocks of quantum logic, schemes of implementation of quantum calculations, as well as some known today effective quantum algorithms, called to realize advantages of quantum calculations upon classical, are concerned. Among them special place is taken by Shor's algorithm of number factorization, Grover's algorithm of unsorted database search and, finally, the most promising in application methods of quantum phenomena simulation, particularly quantum chaos. The most perspective methods of experimental realization of quantum computer, namely nuclear-magnetic resonance and trapped ions realizations, are discussed. Phenomena of decoherence, its influence on quantum computer stability and methods of quantum error correction are described.

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Another short and interesting paper I encountered recently was on the equivalence between the circuit model and adiabatic quantum computing, by Lidar, et al. It can be accessed here. If you are unfamiliar with adiabatic quantum computation, a nice nontechnical introduction by Chris Lee is available here. Then, there's another interesting paper entitled "How Powerful is Adiabatic Quantum Computing?" by van Dam, Mosca and U. Vazirani, from IEEE.

quant-ph/0609163

As a *first* post, let me cite a link which I picked up on Physicsforums (thread: has quantum mechanics changed since the big bang?) earlier today:

quant-ph/0609163

Authors: H. Nikolic
Comments: 28 two-column pages, pedagogic review
Subj-class: Quantum Physics; Physics Education

A common understanding of quantum mechanics (QM) among students and practical users is often plagued by a number of "myths", that is, widely accepted claims on which there is not really a general consensus among experts in foundations of QM. These myths include wave-particle duality, time-energy uncertainty relation, fundamental randomness, the absence of measurement-independent reality, locality of QM, nonlocality of QM, the existence of well-defined relativistic QM, the claims that quantum field theory (QFT) solves the problems of relativistic QM or that QFT is a theory of particles, as well as myths on black-hole entropy. The fact is that the existence of various theoretical and interpretational ambiguities underlying these myths does not yet allow us to accept them as proven facts. I review the main arguments and counterarguments lying behind these myths and conclude that QM is still a not-yet-completely-understood theory open to further fundamental research.