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Jan 28, 2023 at 13:01 history edited YCor CC BY-SA 4.0
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Jan 28, 2023 at 11:17 history edited Ali Taghavi CC BY-SA 4.0
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Jun 15, 2018 at 8:39 vote accept Ali Taghavi
Jun 14, 2018 at 10:24 comment added Robert Bryant Actually, what I said above in the case $n=2$ is not correct because, in the case $n=2$, there are more Killing fields. (See the note in my answer below.) However, when $n>2$ there are no more Killing fields than those generated by the obvious $\mathrm{SO}(n)$-action.
Jun 13, 2018 at 21:56 answer added Robert Bryant timeline score: 6
Jun 13, 2018 at 20:50 comment added Ali Taghavi @RobertBryant I can not understand why Killing vector fields is isometric to the Lie algebra of $SO(n)$. For $n=2$, what is a precise Killing vector field for that metric? This may help me to find all Killing vector fields.
Jun 13, 2018 at 19:14 comment added Ali Taghavi @RobertBryant Yes I was asking for global isometries however your answer about Lie algebra of Killing vector field is very helpful. I try to understand the details of both part. Thanks for this very helpfull comment.
Jun 13, 2018 at 13:53 comment added Robert Bryant Are you asking about global isometries rather than infinitesimal isometries? In the former case, it's just the symmetric group on $n$-letters acting as permutations of the $x_i$ (when $n>1$). The Lie algebra of Killing vector fields, though, has dimension $\tfrac12n(n{-}1)$ (when $n>1$) and is isomorphic to the Lie algebra of $\mathrm{SO}(n)$.
Jun 13, 2018 at 13:40 history edited Ali Taghavi CC BY-SA 4.0
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Jun 13, 2018 at 13:24 history asked Ali Taghavi CC BY-SA 4.0