Related papers: Variations on the SU(5) axion
A class of supersymmetric grand unified theories is introduced that has a single scale below the cutoff, that of the supersymmetry breaking masses $\tilde{m}$. For a wide range of the dimensionless parameters, agreement with the observed…
In topologically massive QED$_{2+1}$ with $N$ flavours, there is the possibility that two equal-charged fermions can form a bound state pair in either s-wave or p-wave. We are concerned about the s-wave pairs and obtain the low energy…
We describe higher-dimensional theories whose low-energy 4D descriptions contain larger gauge or global symmetry groups. As an example, we construct a Higgsless SU(2) x U(1) model of electroweak symmetry breaking. The 5D SU(2) gauge…
In this Lecture we first review the basic properties that make flipped SU(5) a very economical and well motivated unified model, including some recent developments regarding the prediction for $\alpha_s$ and new implications for proton…
We predict the low energy signatures of a Flipped $SU(5) \times U(1)_{\chi}$ effective local model , constructed within the framework of F$-$theory based on $ A_{4} $ symmetry. The Flipped SU(5) model from F Theory in the field of particle…
We study the impact of nonrenormalizable operators in flipped SU(5) that can generate a large mu term, R-parity violation, and rapid proton decay. While our motivation is to determine whether F-theory can naturally realize flipped SU(5),…
Extrapolating the coupling strengths to very high energies, one finds that they do not converge to a single coupling constant, as expected in the simplest gauge theory of Grand Unification, the SU(5) theory. We find that the coupling…
An ${\rm SU}(8)$ theory was previously found to be the minimal simple gauge group where all three-generational Standard Model (SM) fermions can be nontrivially embedded. It is maximally broken into a subgroup of ${\rm SU}(8)\to {\cal…
We discuss the characteristic low energy phenomenological implications of an SU(5) Supersymmetric Grand Unified Theory (SUSY GUT) whose flavour structure is controlled by the family symmetry S4 x U(1), which provides a good description of…
We discuss the lattice formulation of gauge theories with fermions in arbitrary representations of the color group, and present the implementation of the RHMC algorithm for simulating dynamical Wilson fermions. A first dataset is presented…
An SU(2) gauge theory with two fermions transforming under the adjoint representation of the gauge group may appear conformal or almost conformal in the infrared. We use lattice simulations to study the spectrum of this theory and present…
The formulation of a grand unified field theory based on the nonlinearly realized SU(5) gauge group is presented. The tree-level action is constructed by requiring invariance under local left SU(5) gauge transformations, the existence of a…
We consider classical superstrings propagating on AdS_5 x S^5 space-time. We consistently truncate the superstring equations of motion to the so-called su(1|1) sector. By fixing the uniform gauge we show that physical excitations in this…
The axial anomaly arising from the fermion sector of $\U(N)$ or $\SU(N)$ reduced model is studied under a certain restriction of gauge field configurations (the ``$\U(1)$ embedding'' with $N=L^d$). We use the overlap-Dirac operator and…
The N=1 supersymmetric gauge SU(5) theory with one antisymmetric tensor, n+3 fundamentals and n+4 antifundamentals has dual magnetic descriptions in the infrared. By introducing extra singlet fields and tree level superpotential terms to…
We suggest a simple grand unified theory where the fifth dimensional coordinate is compactified on an $S_1/(Z_2 \times Z_2')$ orbifold. This model is based on the supersymmetric flipped $SU(5) \times U(1)$ grand unified theory, which can…
Higher dimensional grand unified theories, with gauge symmetry breaking by orbifold compactification, possess SU(5) breaking at fixed points, and do not automatically lead to tree-level gauge coupling unification. A new framework is…
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…
General SU(2)xSU(2)xU(1) models represent a well-motivated intermediate step towards the unification of the Standard Model gauge groups. Based on a recent global analysis of low-energy and LEP constraints of these models, we perform…
We build a supersymmetric version with $SU(3)_C\otimes SU(2)_L\otimes U(1)_{Y^\prime}\otimes U(1)_{B-L}$ gauge symmetry, where $Y^\prime$ is a new charge and $B$ and $L$ are the usual baryonic and leptonic numbers. The model has three…