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Timeline for $Spin(6,2) = SU(2, 2, \mathbb{H})$

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Jul 31, 2023 at 12:58 answer added Qmechanic timeline score: 0
Oct 3, 2022 at 15:37 comment added Hinanana @runway44 Yes now I agree Spin$(6,2)$ is not SU$(2,2,\mathbb{H})$. In fact we don't have a faithful representation of Spin$(6,2)$: all I know is that Spin(2,6) embeds inside SK$(4, \mathbb{H}) \times$ SK$(4,\mathbb{H})$ (SK$(4,\mathbb{H})$ = SO*$(8)$). See Harvey's book "Spinors and Calibrations".
Oct 1, 2022 at 1:59 comment added anon Is there an elementary description of what this ${\rm SU}(2,2,\Bbb H)$ thing is? My understanding is that the $4\times4$ quaternionic matrices whose transformations of $\Bbb H^4$ preserve the form $|x_1|^2+|x_2|^2−|x_3|^2−|x_4|^2$ make up a $36$-dimensional group which I would call $\rm Sp(2,2)$, but $\rm Spin(6,2)$ is $28$-dimensional so it can't be that. I am particularly interested in if we can see $\rm Spin(5,2)$ or $\rm Spin(6,1)$ in this classical group, or see how $AB$ embeds in it for $A$, $B$ classical groups corresponding to ${\rm Spin}(p,q)$, ${\rm Spin}(r,s)$ and $(p+q,r+s)=(6,2)$.
Feb 15, 2022 at 10:43 vote accept Hinanana
Feb 14, 2022 at 21:27 answer added Torsten Schoeneberg timeline score: 5
Feb 14, 2022 at 16:08 comment added Dietrich Burde Or chapter $6$ here.
Feb 14, 2022 at 15:53 comment added Dietrich Burde I have seen it before (perhaps in Helgason's book). We also have $Spin(6)=SU(4)$ and $Spin(4,2)≃SU(2,2)$. Now take $\Bbb H=\Bbb R^4$. See here.
Feb 14, 2022 at 15:40 comment added Hinanana Don't think so: the reference it gives: Paul Garrett, Sporadic isogenies to orthogonal groups, 2015, does not cover this example. Plus I am not even sure about the authenticity of this statement on wikipedia
Feb 14, 2022 at 15:36 comment added Hinanana Yes. I think they are all theories. Plus I saw another reference request question on here which asked the reference for Spin(4,1) <math.stackexchange.com/questions/1105200/spin-group-spin4-1>
Feb 14, 2022 at 15:33 comment added Dietrich Burde Did you check the references $1.,2.,3.,4.$ of the wikipedia article?
Feb 14, 2022 at 15:24 history asked Hinanana CC BY-SA 4.0