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Conformal invariance of the planar beta-deformed N=4 SYM theory requires beta real

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 نشر من قبل Alberto Santambrogio
 تاريخ النشر 2006
  مجال البحث
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We study the cal{N}=1 SU(N) SYM theory which is a marginal deformation of the cal{N}=4 theory, with a complex deformation parameter beta. We consider the large N limit and study perturbatively the conformal invariance condition. We find that finiteness requires reality of the deformation parameter beta.

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We consider a full Leigh-Strassler deformation of the ${cal N}=4$ SYM theory and look for conditions under which the theory would be conformally invariant and finite. Applying the algorithm of perturbative adjustments of the couplings we construct a family of theories which are conformal up to 3 loops in the non-planar case and up to 4 loops in the planar one. We found particular solutions in the planar case when the conformal condition seems to be exhausted in the one loop order. Some of them happen to be unitary equivalent to the real beta-deformed ${cal N}=4$ SYM theory, while others are genuine. We present the arguments that these solutions might be valid in any loop order.
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