The energy function and homogeneous harmonic maps

Research output: Contribution to journalArticle

Abstract

For equivariant maps from a compact homogeneous space into an adjoint orbit of a compact Lie group, it is shown that the energy function is the restriction of a quadratic function on the Lie algebra, providing the orbit has the metric induced from the Lie algebra. This is related to similar functions studied by R. Bott [2] and by F. C. Kirwan [7]. One obtains a simple version of the harmonic map equation, and an identity relating the energy and the square of the norm of the moment map. Several applications are given, including an example which illustrates how a change of metric in a flag manifold affects the harmonicity of equivariant maps from the two-sphere to the flag manifold.

Original languageEnglish
Pages (from-to)77-98
Number of pages22
JournalProceedings of the London Mathematical Society
Volumes3-62
Issue number1
DOIs
Publication statusPublished - 1991
Externally publishedYes

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Equivariant Map
Flag Manifold
Harmonic Maps
Energy Function
Lie Algebra
Orbit
Moment Map
Metric
Compact Lie Group
Compact Space
Homogeneous Space
Quadratic Function
Restriction
Norm
Energy

ASJC Scopus subject areas

  • Mathematics(all)

Cite this

The energy function and homogeneous harmonic maps. / Guest, Martin.

In: Proceedings of the London Mathematical Society, Vol. s3-62, No. 1, 1991, p. 77-98.

Research output: Contribution to journalArticle

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