Related papers: Trinification and the Strong P Problem
The prediction of the strong coupling constant in grand unified theories is reviewed, first in the standard model, then in the supersymmetric version. Various corrections are considered. The predictions in both supergravity-induced and…
The effects of possible explicit violation of the Peccei-Quinn symmetry responsible for the solution of the strong CP problem are studied in supersymmetric models. It is shown that automatic models with an abelian $U(1)$ gauge symmetry are…
We propose an ${\rm SU}(6)$ unified theory that solves the strong ${\it CP}$ problem with a high-quality axion. This is achieved by an automatic global Peccei-Quinn ${\rm U}(1)_{\rm PQ}$ symmetry and the gauged discrete $\mathbb{Z}_{4{\cal…
We analize the different ways for the spontaneous breaking of the gauge symmetry, for the $[SU(6)]^3\otimes Z_3$ family unification model. In particular we study the consequences of a previous selection for the vacuum expectation values of…
One of the much-debated novel features of theories with extra dimensions is the presence of power-like loop corrections to gauge coupling unification, which have the potential of allowing a significant reduction of the unification scale. A…
We consider a scenario where a supersymmetric model has multiple dark matter particles. Adding a U(1)' gauge symmetry is a well-motivated extension of the Minimal Supersymmetric Standard Model (MSSM). It can cure the problems of the MSSM…
We find that spontaneously broken parity (P) or left-right symmetry stabilizes dark matter in a beautiful way. If dark matter has a non-real intrinsic parity \pm i (e.g. Majorana fermions), parity can ensure that it cannot decay to all…
Given that dark matter and normal matter are nontrivially unified in a grand unified theory, called dark grand unification, we derive novel residual theories at low energy explaining dark matter and neutrino mass. The first chain of which…
In this paper we investigate the problem of spontaneous supersymmetry breaking without a cosmological term in $N=3$ supergravity with matter vector multiplets, scalar fields geometry being $SU(3,m)/SU(3)\otimes SU(m)\otimes U(1)$. At first,…
Since CP violation in weak decays is successfully described by the KM mechanism, the strong CP problem cannot easily be accommodated. This leads us to reconsider the issue. If the axion and massless up quark are abandoned, we must extend…
We investigate the question of parity breaking in three-dimensional Euclidean SU(2) gauge-Higgs theory by Monte Carlo simulations. We observe no sign of spontaneous parity breaking in the behaviour of both local and non-local gauge…
We study effective theories of an axion in spontaneously broken supersymmetric theories. We consider a system where the axion supermultiplet is directly coupled to a supersymmetry breaking sector whereas the standard model sector is…
We consider N=1 supersymmetric gauge theories based on the group SU(N)_1 x SU(N)_2 x ... x SU(N)_k with matter content (N,N*,1,...,1) + (1,N,N*,...,1) + >... + (N*,1,1,...,N) as candidates for the unification symmetry of all particles. In…
We consider 5 dimensional gauge theories where the 5th direction is compactified on an interval. The Chern-Simons (CS) terms (favored by naive dimensional analysis) are discussed. A simple scenario with an extra U(1)_X gauge field that…
We consider supersymmetric theories where the standard-model quark and lepton fields are localized on a "3-brane" in extra dimensions, while the gauge and Higgs fields propagate in the bulk. If supersymmetry is broken on another 3-brane,…
We introduce a new model, the Pyramid Scheme, of direct mediation of SUSY breaking, which is compatible with the idea of Cosmological SUSY Breaking (CSB). It uses the trinification scheme of grand unification and avoids problems with Landau…
GR can be interpreted as a theory of evolving 3-geometries. A recent such formulation, the 3-space approach of Barbour, Foster and \'{O} Murchadha, also permits the construction of a limited number of other theories of evolving…
In this letter we show a kind of \mt gauge symmetry can be unified into a simple group with the standard model gauge symmetry in the context of coset space unification. We also discuss some implication from one of this kind of unification.
We study a five dimensional nonsupersymmetric SU(3) gauge theory compactified on $M^4\times S^1/Z_2$. The gauge hierarchy is discussed in the scenario of the gauge-Higgs unification. We present two models in which the large gauge hierarchy…
A recent paper "What can solve the strong CP problem?" goes counter to conventional wisdom by arguing that the universe was in an initial state that combines different eigenstates of $\theta$ (of the theta vacuum of QCD), and asserts that…