Restriction of A-discriminants and dual defect toric varieties

Hypergeometric Feynman Integrals

“…Configurations A, which having ∆ A (f ) = 1 are called defective. Combinatorial criteria of defective configurations can be found in [71,78,81]. By definition, the A-discriminant is an irreducible polynomial in the coefficients {z a } a∈A , which is uniquely determined up to a sign [105].…”