### KK Reference

#### Posted by Robert H.

I am looking for a reference for the fact that it is impossible to get non-abelian gauge groups or chiral fermions by KK-reduction of 11d sugra on a compact 7-manifold without singularities.
IIRC this was announced by Witten on a conference long ago but so far I have been unsuccesful to dig up the exact reference. Actually, I am more interested in the argument than the original reference, so any other place that proves this is also welcome.
If you know anything about his please leave a comment or send me a mail. Thanks

Posted at November 17, 2005 2:13 PM UTC
## Re: KK Reference

Hi Robert,

I think the Witten reference you are looking for is from the Shelter Island II conference in 1983. His paper “Fermion Quantum Numbers in Kaluza-Klein Theory” was published in the book “Shelter Island II”, MIT Press, 1985, editors Jackiw, Khuri, Weinberg, Witten.