We construct effective Lagrangians of the Veneziano-Yankielowicz (VY) type for two non-supersymmetric theories which are orientifold daughters of supersymmetric gluodynamics (containing one Dirac… (More)

We summarize basic features associated to dynamical breaking of the electroweak symmetry. The knowledge of the phase diagram of strongly coupled theories as function of the number of colors, flavors… (More)

In the large Nc approximation to QCD, the leading ππ scattering amplitude is expressed as the sum of an infinite number of tree diagrams. We investigate the possibility that an adequate approximation… (More)

The LHCb measurement of the μ/e ratio RK∗ indicates a deficit with respect to the Standard Model prediction, supporting earlier hints of lepton universality violation observed in the RK ratio. We… (More)

We propose an all orders beta function for ordinary Yang-Mills theories with or without fermions inspired by the Novikov-Shifman-Vainshtein-Zakharov beta function of N 1⁄4 1 supersymmetric gauge… (More)

PAMELA and ATIC recently reported excesses in e± cosmic rays. Since the interpretation in terms of DM annihilations was found to be not easily compatible with constraints from photon observations, we… (More)

We study the ultraviolet behaviour of four-dimensional quantum field theories involving non-abelian gauge fields, fermions and scalars in the Veneziano limit. In a regime where asymptotic freedom is… (More)

We study a bound state of fractional D3-branes localized inside the world-volume of fractional D7-branes on the orbifold C3/(Z2 × Z2). We determine the open string spectrum that leads to N = 1 U(N1)… (More)

We investigate the physical spectrum of vector-like SU(N) gauge theories with infrared coupling close to but above the critical value for a conformal phase transition. We use dispersion relations,… (More)

We provide a unified description, both at the effective and fundamental Lagrangian level, of models of composite Higgs dynamics where the Higgs itself can emerge, depending on the way the electroweak… (More)