Electroweak Sudakov at two loop level

We investigate the Sudakov double logarithmic corrections to the form facto r of fermion in the SU(2) x U(1) electroweak theory. We adopt the familiar Feynman gauge and present explicit calculations at the two loop level. We s how that the leading logarithmic corrections coming from the infrared singu larities are consistent with the "postulated" exponentiated electroweak Sud akov form factor. The similarities and differences in the "soft" physics be tween the electroweak theory and the unbroken non-abelian gauge theory (QCD ) will be clarified. (C) 2000 Published by Elsevier Science B.V.