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Apr 20, 2020 at 16:30 history edited C.F.G CC BY-SA 4.0
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Oct 1, 2019 at 11:04 comment added Dmitri Panov Sorry, I meant of course $(x^2+y^2+z^2)+...$ - a tiny perturbation of the unite sphere
Sep 23, 2019 at 18:34 vote accept C.F.G
Apr 9, 2021 at 20:37
Sep 23, 2019 at 18:02 comment added Dmitri Panov You can take the following surface in $\mathbb R^3$: $(x^2+y^2+y^2)+10^{-10}(x^3+2y^3+3z^3)=1$. It's group of isometries is trivial.
Sep 22, 2019 at 18:30 comment added C.F.G @SebastianGoette: A perturbed Ricci-positive metric may admits no more isometries? really? do you have any concrete example in your mind?
Sep 22, 2019 at 16:20 comment added Sebastian Goette If you take any Ricci-positive metric and perturb the metric just a little in $C^2$, then the resulting metric is still Ricci-positive and generically admits no more isometries. You could change the question, replacing "of zero-dimensional isometry group" by "which does not admit a smooth effective action by a compact Lie group of dimension $\ge 1$". If a manifold $M$ admits a smooth action by a compact Lie group, then there exists a Riemannian metric on $M$ for which the action is isometric.
Sep 21, 2019 at 16:33 answer added Tsemo Aristide timeline score: 6
Sep 21, 2019 at 16:28 history asked C.F.G CC BY-SA 4.0