Related papers: Gauge coupling beta functions in the Standard Mode…
The effective potential has been previously calculated through three-loop order, in Landau gauge, for a general renormalizable theory using dimensional regularization. However, dimensional regularization is not appropriate for softly broken…
A classically scale-invariant 6d analog of the 4d Yang-Mills theory is the 4-derivative $ (\nabla F)^2 + F^3$ gauge theory with two independent couplings. Motivated by a search for a perturbatively conformal but possibly non-unitary 6d…
All one-loop renormalization constants for Non-Abelian gauge theory are computed in details by using the symmetry-preserving Loop Regularization method proposed in\cite{LR1,LR2}. The resulting renormalization constants are manifestly shown…
The amplitude of Higgs-Higgs interaction is calculated in the Standard Model in the framework of the Sirlin's renormalization scheme in the unitary gauge. The one-loop corrections for lambda, the constant of 4-chi interaction are compared…
In this talk I report on the results of a recent calculation of the \alpha_s corrections to a three-point correlation function at the three-loop level in QCD perturbation theory, which allows one to extract the matrix element of B^0 -\bar…
A family of models for fluctuating loops in a two dimensional random background is analyzed. The models are formulated as O(n) spin models with quenched inhomogeneous interactions. Using the replica method, the models are mapped to the…
The scale-dependent renormalized coupling of SU(3) gauge theory coupled to Nf = 2 flavors of massless Dirac flavors in the sextet representation is presented in the range 0 < g^2 < 6.5. This range includes the location where the…
We present an analytical calculation of the leading three-loop radiative correction to the S-parameter in the Standard Model in the large Higgs mass limit. Numerically, S^(3) = 1.1105*g^4/(1024 pi^3)*m_H^4/M_W^4. When combined with the…
The scale invariant of the effective potential of the standard model at two-loop is used as a boundary condition under the assumption that the two-loop effective potential approximates the full effective potential. This condition leads with…
The two-loop effective action for the SU(3) gauge model in a constant background field ${\bar A}_0(x,t)=B_0^3T_3+B_0^8T_8$ is recalculated for a gauge with an arbitrary $\xi$-parameter. The gauge-invariant thermodynamical potential is found…
The results for the three-loop renormalization group equations for all fundamental parameters of the SM Lagrangian are presented. Special attention is paid to the Flavor sector of the SM, which parameterized by general complex non-diagonal…
In part I and II of this series of papers all elements have been introduced to extend, to two loops, the set of renormalization procedures which are needed in describing the properties of a spontaneously broken gauge theory. In this paper,…
We calculate the two-loop renormalization group equations for the running gaugino masses in general SUSY gauge models, improving our previous result. We also study its consequence to the unification of the gaugino masses in the SUSY SU(5)…
The paper is devoted to the three-loop renormalization of the effective action for a two-dimensional non-linear sigma model using the background field method and a cutoff regularization in the coordinate representation. The coefficients of…
We present the two-loop $\beta$-functions for non-standard soft supersymmetry-breaking couplings including non-standard R-parity violating soft terms in the Minimal Supersymmetric Standard Model
We discuss the renormalization of the electric charge at the two-loop level in the Standard Model of the electroweak interactions. We explicitly calculate the expression of the complete on-shell two-loop counterterm using the Background…
We consider the renormalization group equations within the Standard Model Effective Field Theory and compute two-loop contributions proportional to the top quark Yukawa coupling for the operator generating an effective Higgs-gluon coupling,…
We compute the renormalized running coupling of SU(3) gauge theory coupled to N_f = 2 flavors of massless Dirac fermions in the 2-index-symmetric (sextet) representation. This model is of particular interest as a minimal realization of the…
We present the full two-loop beta-functions for the MSSM including R-parity violating couplings. We analyse the effect of two-loop running on the bounds on R-parity violating couplings, on the nature of the LSP and on the stop masses.
We present a new calculation of the order alpha^2 (Z alpha)^5 correction to the Lamb shift, which uses methods developed for multi-loop calculations.