arXiv subjects
Publications and source records attributed to C. Lovelace.
By lifting full Yang-Mills theory to $R_4 \times S_2$, Mason et al. obtained MHV vertices by gauge transformation. Their Lagrangian depended on long intricate twistor manipulations. Spinor $S_2$ harmonics give a one page proof, eliminating all the $CP_3$ apparatus.
The key to membrane theory is to enlarge the diffeomorphism group until 4D gravity becomes almost topological. Just one ghost survives and its central charges can cancel against matter. A simple bosonic membrane emerges, but its flat D = 28 target space is unstable. Adding supersymmetry ought to give calculable (2,2) membranes in 12 target dimensions, but (2,1) membranes won't work.
The infinite matrices in Witten's vertex are easy to diagonalize. It just requires some SL(2,R) lore plus a Watson-Sommerfeld transformation. We calculate the eigenvalues of all Neumann matrices for all scale dimensions s, both for matter and ghosts, including fractional s which we use to regulate the difficult s=0 limit. We find that s=1 eigenfunctions just acquire a p term, and x gets replaced by the midpoint position.