Related papers: Finite Unification and Top Quark Mass
Gauge and Yukawa (for the third family) coupling unification seem to be the best predictions of the grand-unified theories (GUTs). In supersymmetric GUTs, one also expects that the sparticle masses unify at the GUT scale (for sparticles…
We motivate and explore the possibility that extra SU(N) gauge groups may exist independently of the Standard Model groups, yet not be subgroups of some grand unified group. We study the running of the coupling constants as a potential…
Leptoquarks are theoretically well-motivated and have received increasing attention in recent years as they can explain several hints for physics beyond the Standard Model. In this article, we calculate the renormalisation group evolution…
It is well known that standard gauge theories are renormalizable in D=4 while Einstein gravity is renormalizable in D=2. This is where the research in the field of two derivatives theories is currently standing. We hereby present a class of…
We consider corrections to the unification of down-quark and charged-lepton Yukawa couplings in supersymmetric GUTs, which links the large nu_tau-nu_mu mixing angle to b -> s transitions. These corrections generically occur in simple…
We consider gauge coupling unification in Lee-Wick extensions of the Standard Model that include higher-derivative quadratic terms beyond the minimally required set. We determine how the beta functions are modified when some Standard Model…
We investigate the Higgs-Yukawa system with Majorana masses of a fermion within asymptotically safe quantum gravity. Using the functional renormalization group method we derive the beta functions of the Majorana masses and the Yukawa…
In grand unified theories with large numbers of fields, renormalization effects significantly modify the scale at which quantum gravity becomes strong. This in turn can modify the boundary conditions for coupling constant unification, if…
Higher-dimensional models of grand unification allow us to relate the top Yukawa coupling y_t to the gauge coupling g. The tree level relation y_t=g at the scale of grand unification implies, in the framework of the MSSM, a rather small…
Extra dimension provides an attractive way to break symmetry by boundary conditions which can be useful to construct a natural grand unified theory avoiding the doublet-triplet splitting problem and the proton decay problem. It can provide…
The evolution properties of Yukawa couplings and quark mixings are performed for the one-loop renormalization group equations in the Universal Extra Dimension (UED) model. It is found that the UED model has a substantial effect on the…
In supersymmetric quantum electrodynamics there is the exact relation between the expressed through the unrenormalized coupling gauge beta-function and the anomalous dimension of matter superfields. In the present report we describe the…
In the leading order of a modified 1/Nc expansion, we show that a class of gauge-Higgs-Yukawa systems in four dimensions give non-trivial and well-defined theories in the continuum limit. The renormalized Yukawa coupling y and the quartic…
In a recent paper on SU(16) grand unification, because of the presence of intermediate-energy gauge groups containing products of U(1) factors which are not orthogonal among themselves, the renormalization-group treatment has a few small…
We derive one-loop renormalization group (RG) invariant observables and analyze their phenomenological implications in the MSSM and its \mu problem solving extensions, U(1)' model and NMSSM. We show that there exist several RG invariants in…
A new solution to the requirement of two-loop finiteness of the soft supersymmetry breaking terms (SSB) parameters is found in Finite-Gauge-Yukawa unified theories. The new solution has the form of a sum rule for the relevant scalar masses,…
One way to generate an intermediate scale being consistent with gauge coupling unification is to add new Higgs scalars above the intermediate scale. We classify such scenarios according to their degree of departure from minimal…
We calculate the two-loop matching corrections for the gauge couplings at the Grand Unification scale in a general framework that aims at making as few assumptions on the underlying Grand Unified Theory (GUT) as possible. In this paper we…
We verify a method which allows to obtain the $\beta$-function of supersymmetric theories regularized by higher covariant derivatives by calculating only specially modified vacuum supergraphs. With the help of this method for a general…
The significant heavy threshold effect is found in the supersymmetric SU(5) model with two adjoint scalars, one of which is interpreted as a massive string mode decoupled from the lower-energy particle spectra. This threshold related with…