ALTERNATIVE CONSTRUCTIONS OF CROSSING-SYMMETRIC AMPLITUDES WITH REGGE BEHAVIOR

A representation for the scattering amplitude that contains Regge behavior, crossing symmetry, and analyticity is discussed. It is shown that it provides a different ghost-eliminating mechanism (the Mandelstam-Wang one) from that given by Veneziano's proposal. Furthermore, it does not restrict the external masses, but reduces to Veneziano's formula when α(s)+α(t)+α(u) equals a particular integer that depends on the reaction. Several examples are discussed. The behavior of the Regge residue βρππ(t) at αρ(t)=0 is proposed as a test that distinguishes the two representations. © 1969 The American Physical Society.