Constant Flag Curvature Spaces and Akbar-Zadeh’s Theorem

Abstract

In §3.9, we encountered the flag curvature. As the name suggests, this quantity (denoted K) involves a location x ϵ M, a flagpole ℓ:= with y ϵ T ^x M, and a transverse edge V ϵ T ^x M. The precise formula is quite elegantly given by (3.9.3):

$$K(\ell ,V): = \frac{{{V^i}({\ell ^j}{R_{jikl}}{\ell ^l}){V^k}}}{{g(\ell ,\ell )g(V,V) - {{[g(\ell ,V)]}^2}}} = \frac{{{V^i}{R_{ik}}{V^k}}}{{g(V,V) - {{[g(\ell ,V)]}^2}}}$$

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