ADVANCES IN IMAGING AND ELECTRON PHYSICS VOLUME 129 CALCULUS OF FINITE DIFFERENCES IN QUANTUM ELECTRODYNAMICS EDITOR-IN-CHIEF PETER W. HAWKES CEMES-CNRS Toulouse, France ASSOCIATE EDITORS BENJAMIN KAZAN Xerox Corporation Palo Alto Research Center Palo Alto, California TOM MULVEY Department of Electronic Engineering and Applied Physics Aston University Birmingham, United Kingdom Advances in Imaging and Electron Physics Calculus of Finite Differences in Quantum Electrodynamics HENNING F. HARMUTH Retired, The Catholic University of America Washington, DC, USA BEATE MEFFERT Humboldt-Universitat ¨ Berlin, Germany VOLUME 129 This book is printed on acid-free paper. Copyright © 2003, Elsevier Inc. All Rights Reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information storage and retrieval system, without permission in writing from the Publisher. The appearance of the code at the bottom of the first page of a chapter in this book indicates the Publisher’s consent that copies of the chapter may be made for personal or internal use of specific clients. This consent is given on the condition, however, that the copier pay the stated per copy fee through the Copyright Clearance Center, Inc. (222 Rosewood Drive, Danvers, Massachusetts 01923), for copying beyond that permitted by Sections 107 or 108 of the U.S. Copyright Law. This consent does not extend to other kinds of copying, such as copying for general distribution, for advertising or promotional purposes, for creating new collective works, or for resale. Copy fees for pre-2003 chapters are as shown on the title pages. If no fee code appears on the title page, the copy fee is the same as for current chapters. 1076-5670/2003 $35.00 Permissions may be sought directly from Elsevier's Science & Technology Rights Department in Oxford, UK: phone: (+44) 1865 843830, fax: (+44) 1865 853333, e-mail:
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