DATE: May 11 2005 TIME: 2:00 pm in Weber 202 SPEAKER: Giorgio Ottaviani (Universita di Firenze) TITLE: Hyperdeterminants ABSTRACT: We give a short introduction to hyperdeterminants of multidimensional matrices (hypermatrices) emphasizing their role in the existence of solutions of multilinear systems, which is analogous to the case of usual square matrices. In the case of a 2x2x3 hypermatrix, there is a simple formula for the hyperdeterminant that has easy generalizations in only a few cases. We will characterize "diagonal" and "triangular" hypermatrices and we will give an example of a Vandermonde hypermatrix. We will see how the usual Binet-Cauchy formula has to be modified. Finally, we will give a sketch of the existence of canonical forms whose blocks have sizes given by Fibonacci numbers.