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L A Cordero (Elitor) University of Santiago.de Compostela
Differential geometry
Pitman Advanced Publishing Program LONDON MELBOURNE
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© L A Cordero 1985 First published 1985 53C, 57R30
AMS Subject ISSN 0743-0337
in Publication Data Library of Congress Cataloging Main entry under title:
Differential geometry. (Research notes in mathematics; 131) Proceedings of a colloquium held at Santiago de Compostela, Spain, September 1984. Bibliography: p. 1. Geometry, Differential. 1. Cordero. 1. A 11. Series.
QA641.D383
1985
516.36
85-6350
ISBN 0-273-08708-8 British L'lbraty Cataloguing in Publication Data
Differential geometry.—(Research notes in mathematics, ISSN (1743-0337;131) 1. Geometry, Differential I. Cordero, L.A. II. Series 516.3'6 0A641
iSBN (1-273-08708-8
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Contents
Preface Participants in the Conference PART ONE
:
RIEMANNIAN GEOMETRY
D.E. BLAIR
Critical points of functio'is of the curvature on spaces of associated metrics
1
F.E. BURSTALL
Twistor fibrations of flag manifolds and harmonic maps of a 2-sphere into a
7
J.L. CABRERIZO, M. FERNANDEZ ANDRES
CR—subinanifolds of a locally conformal Kihier manIfold
17
R. CADOED
The Almansi property of the distance function In the Riemannian context
33
C. CURRAS-BOSCH
Infinitesimal transformations with bounded norm
41
EELLS
Certain variational principles in Riemannian geometry
46
F. GOMEZ, M.
The topological dimension of Jhe cut locus
61
GRAY
Ersatz Chern polynomial and Weyl 's tube formula
66
J.F.T. LOPERA
Conformal vector fields on a certain class of nilpotent groups
76
A. MACHADO, I. SALAVESSA
Grassman manifolds as subsets of Euclidean spaces
85
5.14. SALMON
Minimal surfaces and symetric spaces
103
U. SIMON
Eigenvalues of the Laplacian and minimal
J. G-deformations
into spheres
115
and Weyl's tube theorem
121
of surfaces in R3 and R1
138
oF a harmonic morphism
149
S.c.
)LIATION THEORY NT HAL ,
fibre spaces and product decompositions
J. GIRBQJ, M. NICOLALJ
of holoinorphic foliations dnC transversely holomorphic 162
A.
.JGER
of local isometries
174
A.
Generalized foliations and local Lie algebras of Kirillov
198
X. MASA
Cohomology of Lie foliations
211
J. PRADINES
Graph and holonoiny of singular foliations
215
H. SARALEGtJI
The Euler class for flows of Isometries
220
H. SUZUKI
An interpretation of the Well operator x(y1)
228