Geometry, Rigidity, and Group Actions chicago lectures in mathematics series Editors: Spencer J. Bloch, Peter Constantin, Benson Farb, Norman R. Lebovitz, Carlos Kenig, and J. P. May
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Edited by Benson Farb and David Fisher
the university of chicago press • chicago and london Benson Farb is professor of mathematics at the University of Chicago. He is the author of Problems on Mapping Class Groups and Related Topics and coauthor of Noncommutative Algebra. David Fisher is professor of mathematics at Indiana University.
The University of Chicago Press, Chicago 60637 The University of Chicago Press, Ltd., London © 2011 by The University of Chicago All rights reserved. Published 2011 Printed in the United States of America 20191817161514131211 12345
ISBN-13: 978-0-226-23788-6 (cloth) ISBN-10: 0-226-23788-5 (cloth)
Library of Congress Cataloging-in-Publication Data
Geometry, rigidity, and group actions/edited by Benson Farb and David Fisher. p. cm.—(Chicago lectures in mathematics series) Festschrift for Robert Zimmer on the occasion of his 60th birthday. ISBN-13: 978-0-226-23788-6 (cloth : alk. paper) ISBN-10: 0-226-23788-5 (cloth : alk. paper) 1. Rigidity (Geometry) 2. Group actions (Mathematics) 3. Mani- folds (Mathematics) I. Zimmer, Robert J., 1947– II. Farb, Benson. III. Fisher, David. IV. Series: Chicago lectures in mathematics series. QA613.G465 2011 516 .11—dc22 2010026631