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Mar 2, 2015 at 1:05 vote accept Joonas Ilmavirta
Feb 26, 2015 at 20:45 answer added Joonas Ilmavirta timeline score: 1
Oct 9, 2014 at 7:02 comment added Joonas Ilmavirta @AliTaghavi, if you take any bi-invariant Riemannian metric on $G$, then the periodic geodesics passing through the identity are precisely the nontrivial homomorphisms $S^1\to G$. Every Lie subgroup is totally geodesic because of this algebraic structure.
Oct 8, 2014 at 19:38 comment added Ali Taghavi @JoonasIlmavirta In particular, is every torus subgroup, totally geodesic?
Oct 8, 2014 at 19:22 comment added Ali Taghavi @JoonasIlmavirta I am sorry if my question is trivial. Why the image of $\gamma$ is geodesic?
Jul 21, 2014 at 3:03 review First posts
Jul 21, 2014 at 5:10
Jul 20, 2014 at 17:32 comment added Joonas Ilmavirta @Venkataramana True, but the second question can have an affirmative answer even for a faithful representation. If $G=SU(3)$ and $\rho$ is the tautological representation, the geodesic $\gamma(w)=\text{diag}(w,\bar w,1)$ gives $I(\rho,\gamma)=\text{diag}(0,0,1)$. Summing three matrices like this gives an invertible one. I don't know how general this phenomenon is.
Jul 20, 2014 at 17:03 comment added Venkataramana If the representation is faithful, then there is no such geodesic. This follows from Figuera-O'Farrel's answer below, since the integral is zero unless the element $\rho (\gamma) $ is identity.
Jul 20, 2014 at 16:09 answer added José Figueroa-O'Farrill timeline score: 3
Jul 20, 2014 at 14:07 history asked Joonas Ilmavirta CC BY-SA 3.0