Related papers: Three-loop field renormalization for scalar field …
We compute the beta-function and the anomalous dimension of all the non-derivative operators of the theory up to three-loops for the most general nearest-neighbour O(N)-invariant action together with some contributions to the four-loop…
A comprehensive study is performed of general massive, scalar, two-loop Feynman diagrams with three external legs. Algorithms for their numerical evaluation are introduced and discussed, numerical results are shown for all different…
We compute the three loop MSbar anomalous dimension for the 3-quark operator corresponding to the proton. This requires the treatment of gamma^5 within dimensional regularization as well as evanescent operators generated through the…
Perturbative expansions of relativistic quantum field theories typically contain ultraviolet divergences requiring regularization and renormalization. Many different regularization techniques have been developed over the years, but most…
We study systematically, through two loops, the divergence structure of the supersymmetric WZ model defined on the N=1/2 nonanticommutative superspace. By introducing a spurion field to represent the supersymmetry breaking term F^3 we are…
Scattering amplitudes at loop level can be expressed in terms of Feynman integrals. The latter satisfy partial differential equations in the kinematical variables. We argue that a good choice of basis for (multi-)loop integrals can lead to…
The quantum action for a three-dimensional real sextic model using the background field method is considered. Four-loop renormalization of this model is performed with a cutoff regularization in the coordinate representation. The…
We demonstrate the effectivity of the covariant background field method by means of an explicit calculation of the 3-loop beta-function for a pure Yang-Mills theory. To maintain manifest background invariance throughout our calculation, we…
We calculate the integrated trace anomaly for a real spin-0 scalar field in six dimensions in a torsionless curved space without a boundary. We use a path integral approach for a corresponding supersymmetric quantum mechanical model. Weyl…
We consider a general d=4 N=1 globally supersymmetric lagrangian involving chiral and vector superfields, with arbitrary superpotential, Kahler potential and gauge kinetic function. We compute perturbative quantum corrections by employing a…
Using functional renormalization methods, we study the one-loop renormalization group evolution of theories with four scalars, at second order in the derivative expansion, in which electroweak symmetry is nonlinearly realized. In this…
Identification of the diagrams that can lead to gauge anomalies in the (minimal) Lorentz- and $CPT$-violating extension of quantum electrodynamics reveals these are the electron self-energy and vertex correction (related to the…
We use the background-field method and the heat kernel to obtain all counterterms to two-loop order of conformally-coupled multiflavor $\phi^3$ theory in six spacetime dimensions, defined in curved spacetime and with spacetime-dependent…
We show that the general Lorentz- and CPT-violating extension of quantum electrodynamics is one-loop renormalizable. The one-loop Lorentz-violating beta functions are obtained, and the running of the coefficients for Lorentz and CPT…
Various studies have already considered radiative corrections in Lorentz-violating models unveiling many instances where a minimal or nonminimal operator generates, via loop corrections, a contribution to the photon sector of the…
In this paper, we formulate the Lorentz-breaking extension for the spin-3/2 field theory and couple it to the Abelian gauge field in a Lorentz violating (LV) manner. Next, we calculate the lower LV quantum corrections, that is, the…
We propose a framework for calculating two-loop Feynman diagrams which appear within a renormalizable theory in the general mass case and at finite external momenta. Our approach is a combination of analytical results and of high accuracy…
We compare quantum corrections to semiclassical spinning strings in AdS(5)xS(5) to one-loop anomalous dimensions in N=4 supersymmetric gauge theory. The latter are computed using the reduced (Landau-Lifshitz) sigma model and with the help…
We consider general renormalizable scalar field theory and derive six-loop beta functions for all parameters in d = 4 dimensions within the $\overline{MS}$-scheme. We do not explicitly compute relevant loop integrals but utilize…
Dimensional Reduction is applied to \qcd{} in order to compute various renormalization constants in the \drbar{} scheme at higher orders in perturbation theory. In particular, the $\beta$ function and the anomalous dimension of the quark…