In this paper the diierent algebraic varieties that can be generated from multiple view geometry with uncalibrated cameras have been investigated. The natural descriptor, Vn, to work with is the image of IP 3 in IP 2 I P 2 I P 2 under a corresponding product of projections, (A1 A2 : : :Am). Another descriptor, the variety V b , is the one generated by all bilinear forms between pairs of views, ...

We conjecture a topology changing transition in M-theory on a non-compact asymptotically conical Spin(7) manifold, where a 5-sphere collapses and a CP bolt grows. We argue that the transition may be understood as the condensation of M5-branes wrapping S5. Upon reduction to ten dimensions, it has a physical interpretation as a transition of D6-branes lying on calibrated submanifolds of flat spac...