2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/204673A new class of twistor string theories were recently constructed by Abou-Zeid, Hull and Mason. The most interesting one of these theories has the particle content of N=8 supergravity. Arguments are given for the vanishing of the (+ - -)-helicity amplitude for gravitons which suggest that this theory describes a chiral N=8 supergravity rather than Einstein supergravity.10 pagesHigh Energy Physics - Theorytext