M/E23

The study of the relationship between the cone of positive semidef- inite (psd) real forms and its subcone of sums of squares (sos) of forms goes back to the 1888 seminal paper of Hilbert, where he gave a complete charac- terisation of the pairs (n,2d) for which a psd n-ary 2d-ic form can be written as sos. In this talk, I will show how this relationship changes under the addi- tional assumptions of symmetry. I will present our recent results giving the analogues of Hilbert's characterisation for symmetric and even symmetric forms respectively. (Joint work with S. Kuhlmann and B. Reznick)

Dr. Charu Goel

IISER Mohali