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Comments on the Background Field Method in Harmonic Superspace: Non-holomorphic Corrections in N=4 SYM

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 نشر من قبل Sergey M. Kuzenko
 تاريخ النشر 1998
  مجال البحث
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We analyse the one-loop effective action of N=4 SYM theory in the framework of the background field formalism in N=2 harmonic superspace. For the case of on-shell background N=2 vector multiplet we prove that the effective action is free of harmonic singularities. When the lowest N=1 superspace component of the N=2 vector multiplet is switched off, the effective action of N=4 SYM theory is shown to coincide with that obtained by Grisaru et al on the base of the N=1 background field method. We compute the leading non-holomorphic corrections to the N=4 SU(2) SYM effective action.

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