pi NN and pseudoscalar form factors from lattice QCD.
The {pi}{ital NN} form factor {ital g}{sub {pi}{ital NN}}({ital q}{sup 2}) is obtained from a quenched lattice QCD calculation of the pseudoscalar form factor {ital g}{sub {ital P}}({ital q}{sup 2}) of the proton with pion pole dominance. We find that {ital g}{sub {pi}{ital NN}}({ital q}{sup 2}) is well fitted with a monopole form which agrees with the Goldberger-Treiman relation. The monopole mass is determined to be 0.75{plus_minus}0.14 GeV, which shows that {ital g}{sub {pi}{ital NN}}({ital q}{sup 2}) is rather soft. The extrapolated {pi}{ital N} coupling constant {ital g}{sub {pi}{ital NN}}=12.7{plus_minus}2.4 is quite consistent with the phenomenological values. We also compare {ital g}{sub {pi}{ital NN}}({ital q}{sup 2}) with the axial form factor {ital g}{sub {ital A}}({ital q}{sup 2}) to check pion dominance in the induced pseudoscalar form factor {ital h}{sub {ital A}}({ital q}{sup 2}) vis-a-vis the chiral Ward identity.