Almost Positive Curvature on the Gromoll-meyer Sphere
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چکیده
Gromoll and Meyer have represented a certain exotic 7-sphere Σ as a biquotient of the Lie group G = Sp(2). We show for a 2-parameter family of left invariant metrics on G that the induced metric on Σ has strictly positive sectional curvature at all points outside four subvarieties of codimension ≥ 1 which we describe explicitly.
منابع مشابه
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تاریخ انتشار 2008