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Timeline for The finite subgroups of SU(n)

Current License: CC BY-SA 4.0

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Nov 11, 2022 at 0:00 comment added Ian Gershon Teixeira That was really helpful! I used it to write up math.stackexchange.com/questions/4539427/… . I'm not expecting an answer to this but if you know any references for finite subgroups of $ SO_7(\mathbb{R}) $ I would be very interested to see them!
Sep 27, 2022 at 9:06 comment added José Figueroa-O'Farrill @IanGershonTeixeira Not sure right now. However, since the universal cover of $SO_5(\mathbb{R})$ is $\operatorname{Spin}(5) \cong \operatorname{Sp}(2)$, you may be able to look for finite subgroups of $2 \times 2$ quaternionic matrices. A quick google came up with this: core.ac.uk/download/pdf/82740228.pdf
Sep 26, 2022 at 17:08 comment added Ian Gershon Teixeira Thanks for the code it was very interesting! Recently I've been interested in finite subgroups of $ SO_5(\mathbb{R}) $. Would you happen to know any references that discuss the finite subgroups of $ SO_5(\mathbb{R}) $? For example you mentioned that an algorithm of Zassenhaus has been used on $ SO_n $ for at least $ n=6 $.
Jun 3, 2022 at 8:05 history edited Glorfindel CC BY-SA 4.0
broken link fixed, cf. https://math.meta.stackexchange.com/a/34713/228959
Mar 2, 2022 at 8:37 comment added José Figueroa-O'Farrill @IanGershonTeixeira I'm afraid it's not particularly well documented, but here it is: dropbox.com/s/63drrattjugkzo7/SU3subgroupOrder360Again.nb?dl=0
Apr 2, 2010 at 19:47 history edited José Figueroa-O'Farrill CC BY-SA 2.5
added 345 characters in body
Apr 2, 2010 at 14:23 comment added José Figueroa-O'Farrill Indeed -- I just had Mathematica check the order of the group generated by the explicit SU(3) matrices in the paper of Fairbairn et al. and it has order 1080.
Apr 2, 2010 at 6:07 comment added Dylan Thurston Reading a little more closely, it seems that the group with the 3-dimensional representation is not $A_6$, but rather a $\mathbb{Z}/3$ central extension of $A_6$.
Apr 2, 2010 at 0:44 comment added José Figueroa-O'Farrill Apparently it is sci.math, not sci.math.research -- sorry. How I wish I could edit comments!
Apr 2, 2010 at 0:44 comment added José Figueroa-O'Farrill I forgot to link to the sci.math.research thread. Here it is: sci.tech-archive.net/Archive/sci.math/2005-03/5511.html
Apr 1, 2010 at 22:32 comment added José Figueroa-O'Farrill In fact, this statement already appears in the book of Blichfeldt, Dickson and Miller which Bruce Westbury mentions in his answer. It is claimed that this group is simple. There is a thread in sci.math.research claiming that any simple group of order 360 is isomorphic to $A_6$. If so, then the mistake is in claiming that the group is simple, because as you point out, $A_6$ has no nontrivial representation of dimension 3. (The smallest is of dimension 5.) I must admit that I have not gone through their proof, so cannot say where the error lies.
Apr 1, 2010 at 6:24 comment added Dylan Thurston The Fairbairn, Fulton and Klink paper has at least one error: they claim that $A_6$ appears as a finite subgroup of $\mathrm{SU}(3)$, but $A_6$ has no 3-dimensional representations, as indeed their character table shows. What is the group of order 360 that appears?
Mar 18, 2010 at 16:22 vote accept Q.Q.J.
Mar 4, 2010 at 13:30 history edited José Figueroa-O'Farrill CC BY-SA 2.5
Added some links
Mar 4, 2010 at 11:51 history edited José Figueroa-O'Farrill CC BY-SA 2.5
added 243 characters in body
Mar 4, 2010 at 11:44 history answered José Figueroa-O'Farrill CC BY-SA 2.5