A geometric construction of Tango bundle on P^5

Abstract

The Tango bundle T over P^5 is proved to be the pull-back of the twisted Cayley bundle C(1) via a map f : P^5 --> Q_5 existing only in characteristic 2. The Frobenius morphism F factorizes via such f. Using f the cohomology of T is computed in terms of F^*(C), Sym^2(C), C and the tensor product of S by C, while these are computed by applying Borel-Bott-Weil theorem. By machine-aided computation the mimimal resolutions of C and T are given; incidentally the matrix presenting the spinor bundle S over Q_5 is shown.