We derive an explicit Hamiltonian for copying the basis up and down states of a quantum two-state system—a qubit—onto n " copy " qubits (n ≥ 1) initially all prepared in the down state. In terms of spin components , for spin-1 2 particle spin states, the resulting Hamiltonian involves n-and (n + 1)-spin interactions. The case n = 1 also corresponds to a quantum-computing controlled-NOT gate.

In this paper we discuss techniques to copy overlapping terms. Starting from the classical Cheney-style copying algorithm, we present several refinements that exploit compact terms where a structure’s last argument overlaps with the following structure. Finally, a two pass algorithm is presented that uses less auxiliary space and that exploits all possible overlaps for finite terms. In spite of...

Study of the history of programming languages reveals a subtle interplay between semantics and implementation. Early languages, designed for maximum eeciency, provided simple abstractions of the underlying hardware. These languages were followed by languages that were \problem oriented" in that they attempted to hide the grosser details of the underlying hardware. Yet confusion between semantic...

This is an overview of the economics of copying and copyright for the Journal of Economic Perspectives.

Garbage collectors must minimize the scarce resources of cache space and off-chip communications bandwidth to optimize performance on modern single-chip computer architectures. Strategies for achieving these goals in the context of copying garbage collection are discussed. A multi-processor mutator/collector system is analyzed. Finally, the Intel 80860XP architecture is studied.

V. Bužek, S. L. Braunstein, M. Hillery, and D. Bruß 1 Optics Section, The Blackett Laboratory, Imperial College, London SW7 2BZ, United Kingdom 2 Institute of Physics, Slovak Academy of Sciences, Dubravská cesta 9, 842 28 Bratislava, Slovakia 3 University of Wales, Dean Street, Bangor LL57 1UT, United Kingdom 4 Department of Physics and Astronomy, Hunter College, CUNY, 695 Park Avenue, New York...

resilience as a psychological emotional mechanism is employed by the individuals when they are in stressful irritating situations to be able to resume their previous productive mental activities. it is a vital coping activity when students go through upsetting events, psychological breakdowns, academic failures, suffocating educational atmospheres, and undemocratic teaching techniques. the esse...

conclusions the persian handwriting assessment tool as a comprehensive and quickly scored tool that can help therapists identify primary school students with handwriting problems so that appropriate interventions for these students can be implemented. methods this methodological study was conducted in tehran, iran during 2015 - 2016. measurement items were selected by reviewing the past literat...

Automatic verbatim coding technology is essential in many contexts in which, either because of the sheer size of the dataset we need to code, or because of demanding time constraints, or because of cost-effectiveness issues, manual coding is not a viable option. However, in some of these contexts the accuracy standards imposed by the customer may be too high for today’s automated verbatim codin...