Validity of Sum Rules and High Energy Theorems by Current Algebra
Yukio Taguchi, Kohei Yamamoto · Progress of Theoretical Physics · 1967
Sum rules and high energy theorems by current algebra are checked by a free field (lowest order in perturbation) model. It seems that, from the commutation relations [\int Viαd3x, \intVjβd3x], [\int xiV0αd3x, \int Vjβd3x] and [\int Pαd3x, \int Pβd3x] we cannot obtain any sum rule or high energy theorem, whereas [\int xiV0αd3x, \int xiV0βd3x] and [\int A0αd3x, \int A0βd3x] give correct sum rules, where Vµ, Aµ, P are the vector, axial vector, pseudo-scalar currents and α, β are SU(2) or SU(3) index.