Slides used by many of the lecturers at the recent Davis mathematical physics conference in honor of Albert Schwarz are now online.
Slides used by many of the lecturers at the recent Davis mathematical physics conference in honor of Albert Schwarz are now online.
I’m just getting this from Lawson-Michelson, Spin Geometry, Theorem 8.4, Chapter I, where they also get the cover correct.
Hmm I thought the double (actually 4-fold) cover for SO(p,q) was Spin(p,q)…how did you pull out SL(4,R)?
The Clifford algebra Cl(3,3) does have a “Weyl”-like representation
Bmu = [[ 0, gamma_mu ],[ gamma_mu, 0 ]]
B5 = [[ 0, -gamma_5 ],[ -gamma_5, 0 ]]
B6 = [[ 0, i ],[ -i, 0 ]]
and since the gammas have a purely imaginary (Majorana) representation (for spacetime = —+) I can see SL4R coming in…
I don’t really know anything about SO(3,3). It’s not the conformal symmetry group of Minkowski space. Its spin double cover is not SU(2,2), but SL(4,R). The tricks Witten is talking about that get representations of SU(2,2) by “quantizing” C^4 and using the action of SU(2,2) on C^4 won’t work for SO(3,3).
How does the whole argument change if we start with SO(3,3)?
He never really got to talking strings. In the last part of his talk he was just explaining his formula for gauge theory scattering amplitudes as integrals over 2d-subspaces D (actually algebraic curves of genus zero) in CP^3. You can try and interpret these curves as world-sheets of strings, but he didn’t get into that in this talk.
3/4s of Witten’s talk was fun (I think it’s just a rehash of Penrose) but he lost me when he started talking strings. What was his point?