M-theory conifolds -: art. no. 121602

Seven manifolds of G(2) holonomy provide a bridge between M-theory and string theory, via Kaluza-Klein reduction to Calabi-Yau six manifolds. We find first-order equations for a new family of G(2) metrics D-7, with S-3 x S-3 principal orbits. These are related at weak string coupling to the resolved conifold, paralleling earlier examples B-7 that are related to the deformed conifold, allowing a deeper study of topology change and mirror symmetry in M-theory. The D-7 metrics nontrivial parameter characterizes the squashing of an S-3 bolt, which limits to S-2 at weak coupling. In general the D-7 metrics are asymptotically locally conical, with a nowhere-singular circle action.