The relation between the trace and R-current anomalies in supersymmetric
theories implies that the U(1)R​F2, U(1)R​ and U(1)R3​ anomalies which
are matched in studies of N=1 Seiberg duality satisfy positivity constraints.
Some constraints are rigorous and others conjectured as four-dimensional
generalizations of the Zamolodchikov c-theorem. These constraints are tested
in a large number of N=1 supersymmetric gauge theories in the non-Abelian
Coulomb phase, and they are satisfied in all renormalizable models with unique
anomaly-free R-current, including those with accidental symmetry. Most striking
is the fact that the flow of the Euler anomaly coefficient, aUV​−aIR​, is
always positive, as conjectured by Cardy.Comment: latex, 36 page