Light dilaton at fixed points and ultra light scale super-Yang-Mills

We investigate the infrared dynamics of a nonsupersymmetric SU(X) gauge theory featuring an adjoint fermion, N-f Dirac flavors and a Higgs-like complex N-f x N-f scalar which is a gauge singlet. We first establish the existence of an infrared stable perturbative fixed point and then investigate the spectrum near this point. We demonstrate that this theory features a light scalar degree of freedom to be identified with the dilaton and elucidate its physical properties. We compute the spectrum and demonstrate that at low energy the nonperturbative part of the spectrum of the theory is the one of pure supersymmetric Yang-Mills. We can therefore determine the exact nonperturbative fermion condensate and deduce relevant properties of the nonperturbative spectrum of the theory. We also show that the intrinsic scale of super-Yang-Mills is exponentially smaller than the scale associated to the breaking of conformal and chiral symmetry of the theory. (C) 2012 Elsevier B.V. All rights reserved.