منابع مشابه
Topological Restrictions for Circle Actions and Harmonic Morphisms
Let M be a compact oriented smooth manifold which admits a smooth circle action with isolated fixed points which are isolated as singularities as well. Then all the Pontryagin numbers of M are zero and its Euler number is nonnegative and even. In particular, M has signature zero. We apply this to obtain non-existence of harmonic morphisms with one-dimensional fibres from various domains, and a ...
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We show that under some non-degeneracy assumption the only submersive harmonic morphism on a conformally flat 3−sphere is the Hopf fibration. The proof involves an appropriate use the Chern-Simons functional.
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ژورنال
عنوان ژورنال: Conformal Geometry and Dynamics of the American Mathematical Society
سال: 1999
ISSN: 1088-4173
DOI: 10.1090/s1088-4173-99-00026-0