CODEN: RMPHATISSN: 0034-6861

Reviews
of
Modern
Physics
Editorial Office

Reviews of Modern Physics
Department of Physics
University of Washington
Box 351560
Seattle, WA 98195-1560

Fax: (206) 543-6782
E-Mail: rmp@phys.washington.edu
http://www.phys.washington.edu/~rmp/

RMP Online

http://rmp.aps.org
A quarterly journal published by The American Physical Society,
Martin Blume, Editor-in-Chief.

Editor: George F. Bertsch, Department of Physics, University of Washington, Seattle, WA 98195

Reviews of Modern Physics seeks to enhance communication among physicists by
publishing comprehensive scholarly reviews of significant topics, as well as
colloquia and tutorial articles in rapidly developing fields of physics.

Colloquium Editor: Anthony F. Starace, Dept. of Physics & Astronomy, University of Nebraska, Lincoln, NE 68588-0111

Associate Editors:
L. A. Bloomfield, Department of Physics, University of Virginia, Charlottesville, VA 22904-4714
D. M. Ceperley, Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801
M. Dine, Department of Physics, University of California, Santa Cruz, CA 95064
A. M. Goldman, Department of Physics, University of Minnesota, Minneapolis, MN 55455
P. B. Littlewood, Cavendish Laboratory, University of Cambridge, Cambridge CB3 OHE, United Kingdom
K. Nakamura, Institute of Particle and Nuclear Studies, KEK (High Energy Accelerator
    Research Organization), Oho, Tsukuba, Japan
M. Neubert, Department of Physics, Cornell University, Ithaca, New York 14853-2501
A. Richter, Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
R. H. Siemann, Stanford Linear Accelerator Center, Menlo Park, CA 94025
V. Trimble, Department of Physics, University of California, Irvine, CA 92697-4575 and
    Department of Astronomy, University of Maryland, College Park, MD 20742-2421
P. Zoller, Institute of Theoretical Physics, Universität Innsbruck, 6020 Innsbruck, Austria

Assistant Editor: Karie Friedman
Production Division Editors: Doug Parker, Heather Callahan


Subscription Prices
Information regarding subscription prices, including reduced prices for members of the American Physical Society, members of AIP societies, and members of APS reciprocal societies (cooperating foreign physical societies) is provided on the RMP website, http://rmp.aps.org/subscriptions.html.

Copyright © 2001, The American Physical Society. Permission to quote excerpts or to reprint any figures or tables should be obtained directly from an author. The American Physical Society for its part hereby grants permission to quote excerpts and reprint figures and/or tables from its journals with acknowledgment of the sources. Individual teachers, students, researchers, and libraries in nonprofit institutions acting for them are permitted to make hard copies of articles for use in teaching or research, provided such copies are not sold. Copying of articles for sale by document delivery services or suppliers, or beyond the free copying allowed above, is permitted against payment of a copying fee, which is $20.00 plus $0.20 per page. This fee for document delivery services is shown at the bottom of the first page of each article. Express permission of APS is not required, except for purposes stated below, provided that the fee is paid through the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923. Contact the CCC for information on how to report copying and remit payments. Reproduction in a reprint collection, or for advertising or promotional purposes, or republication in any form requires permission of one of the authors and a license from APS. Such a license must be sought from Barbara Hicks, Associate Publisher, The American Physical Society, One Physics Ellipse, College Park, MD 20740-3844. Permission of the author must be obtained from him or her directly.

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