Department of MathematicsAbstract: Closed manifolds admitting non-negative sectional curvature are not very well understood and it is, at present, quite difficult to obtain examples with interesting topology. This is partially explained by the dearth of known constructions, all of which depend in some way on two basic facts: First, compact Lie groups admit a bi-invariant metric (hence, non-negative curvature) and, second, Riemannian submersions do not decrease sectional curvature. In a recent paper, we (S. Goette, M. Kerin and K. Shankar) constructed an infinite, 7-dimensional family of 2-connected, 7-manifolds which have the cohomology of an S^3-bundle over S^4. This family includes all S^3-bundles over S^4, as well as all homotopy 7-spheres (by the previous seminal work of Grove and Ziller all S^3-bundles over S^4 were known to admit non-negative curvature which includes 20 out of 28 homotopy 7-spheres). In a subsequent paper we showed, by computing a secondary invariant, that this family also includes manifolds with non-standard linking form i.e., 2-connected, 7-manifolds which are cohomology S^3-bundles over S^4 admitting non-negative curvature, but not even homotopy equivalent to any S^3-bundle over S^4. In this talk we will present the construction of these new examples. As mentioned above this is joint work with Sebastian Goette and Martin Kerin.