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Nov 28, 2022 at 21:59 comment added Sam Nead @MoisheKohan - could I ask you (pretty please!) to (try to) avoid "biting the hyperbolic geometry newbies"? Thank you!
Nov 28, 2022 at 18:49 comment added ThiKu @Moishe Kohan: Most people think of hyperbolic space as a concrete model, say upper half space or disk model. The notation as a homogeneous space is then just a short way to define it.
Nov 28, 2022 at 16:04 answer added IJL timeline score: 6
Nov 28, 2022 at 14:15 comment added David.D It is true that I am not very familiar with hyperbolic geometry. I copied the above description from wikipedia without checking. The version I am interested in is $\operatorname{SO}^\circ(3,1)/\operatorname{SO}(3)$ where $\operatorname{SO}^\circ(3,1)$ is the connected component that contains the identity.
Nov 28, 2022 at 13:54 comment added Moishe Kohan It does not seem like you know the actual definition because what's written now is not even wrong but meaningless. If you want to describe $H^3$ as a quotient of a simple Lie group by its maximal compact subgroup, you should first decide if you consider orientation-preserving or all isometries. In the former case, you could use $PSL(2,C)/SO(3)$, in the latter case you could use $PO(3,1)/PO(3)$.
Nov 28, 2022 at 12:20 comment added ThiKu Well, now O(3) is not a subgroup of SO(3,1). But we all know, what is meant.
Nov 28, 2022 at 10:40 history edited David.D CC BY-SA 4.0
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Nov 28, 2022 at 10:19 comment added David.D You are right! I have edited the question again.
Nov 28, 2022 at 10:17 history edited David.D CC BY-SA 4.0
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Nov 28, 2022 at 10:12 comment added Moishe Kohan Well, it is still wrong, with your new definition $H^3$ has two connected components!
Nov 28, 2022 at 8:29 history edited YCor
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Nov 28, 2022 at 7:50 comment added David.D It is a typo. I have edited the questions.
Nov 28, 2022 at 7:45 history edited David.D CC BY-SA 4.0
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Nov 28, 2022 at 6:39 comment added ThiKu I guess it’s a typo. SO(3) in place of SO(1) will be fine.
Nov 28, 2022 at 4:23 history became hot network question
Nov 28, 2022 at 1:30 comment added Moishe Kohan Your definition of the hyperbolic 3-space is plain wrong.
Nov 27, 2022 at 21:22 vote accept David.D
Nov 27, 2022 at 21:06 answer added Sam Nead timeline score: 15
Nov 27, 2022 at 20:22 history asked David.D CC BY-SA 4.0