A Sparse Version of Reznick's Positivstellensatz

Ngoc Hoang Anh Mai, Victor Magron, Jean B. Lasserre

Abstract: If f is a positive definite form, Reznick’s Positivstellensatz states that there exists k∈N such that ‖x‖22kf is a sum of squares of polynomials. Assuming that f can be written as a sum of forms ∑l...