Related papers: Radical Conservatism and Nucleon Decay
The unification of gauge couplings suggests that there is an underlying (supersymmetric) unification of the strong, electromagnetic and weak interactions. The prediction of the unification scale may be the first quantitative indication that…
Supersymmetric grand unified theories based on the gauge group SO(10) are highly motivated. In the simplest models, one expects t-b-\tau Yukawa coupling unification, in addition to gauge, matter and Higgs unification. Yukawa unification…
We review the status of a class of gauge unified models based on SO(10) group. After a pedagogical introduction to SO(10) gauge theories, we discuss the main phenomenological implications of these models. The upper limit on proton lifetime…
Although continuous symmetries may be more appealing, especially the local gauge ones, I argue that discrete symmetries may still play a fundamental role in shaping our understanding of the physics beyond the Standard Model. I exemplify…
Massive neutrinos are a generic prediction of SO(10), and models of unification cry for supersymmetry. Since we have a rather detailed information on neutrino and charged fermion masses, the real question is: how/whether it is possible to…
It is noted that one is now in possession of a set of facts, which may be viewed as the matching pieces of a puzzle ; in that all of them can be resolved by just one idea - that is grand unification. These include : (i) the observed…
We investigate Higgs Parity Unification-a realization of $SO(10)$ grand unification based on the Higgs Parity mechanism in which the Standard Model (SM) Higgs resides in a spinor representation. The theory has an intermediate left-right…
By way of paying tribute to Abdus Salam, I recall the ideas of higher unification that he and I initiated. I discuss the current status of those ideas in the light of recent developments, including those of: (a) gauge coupling unification,…
In direct breaking of non-supersymmetric SO(10) to the standard model, we investigate the possibility that dark matter (DM) decaying through its mixing with right-handed neutrino (RH$\nu$) produces high energy IceCube neutrinos having…
Gauge Higgs Unification in Warped Extra Dimensions provides an attractive solution to the hierarchy problem. The extension of the Standard Model gauge symmetry to $SO(5)xU(1)_X$ allows the incorporation of the custodial symmetry $SU(2)_R$…
The supersymmetric decays of the top quark into charged Higgs plus bottom, $\thb$, and into the supersymmetric partner of the top (${\wti u}_1$) plus the lightest neutralino (${\wti \chi}_1^0$), $\tstopneu$, are discussed within the…
The initial data on the production and decay of the Higgs boson reported significant deviations from the Standard Model (SM) expectations, prompting much speculation about its couplings to the other particles. Although the latest data has…
In dense neutrino backgrounds present in supernovae and in the early Universe neutrino oscillations may exhibit complex collective phenomena, such as synchronized oscillations, bipolar oscillations and spectral splits and swaps. We consider…
It is well known that the minimal renormalizable $SU(5)$ grand unified theory is ruled out: it predicts same masses of down quarks and charged leptons, the gauge couplings do not unify and neutrinos are massless. We show here that all this…
In the context of the $\mathrm{SU(3)_c \otimes SU(3)_L \otimes U(1)_X \otimes U(1)_{N}}$ (3-3-1-1) extension of the standard model, we show how the spontaneous breaking of the gauge symmetry gives rise to a residual symmetry which accounts…
Neutrino and charged fermion masses provide important constraints on grand unified theories. We illustrate this by focusing on a renormalizable, supersymmetric SO(10) theory proposed long ago, that recently attracted great interest in view…
It is shown that a supersymmetric SO(10) model extended with fermion singlets can accommodate the observed neutrino masses and mixings as well as generate the desired lepton asymmetry in concordance with the gravitino constraint. A…
A structure is proposed for the mass matrices of the quarks and leptons that arises in a natural way from the assumption that the breaking of SO(10) gauge symmetry is achieved by the smallest possible set of vacuum expectation values. This…
We construct models of warped unification with a bulk SO(10) gauge symmetry and boundary conditions that preserve the SU(4)_C x SU(2)_L x SU(2)_R Pati-Salam gauge group (422). In the dual 4D description, these models are 422 gauge theories…
The couplings of the low scale type I see-saw model are severely constrained by the requirement of reproducing the correct neutrino mass and mixing parameters, by the non-observation of lepton number and charged lepton flavour violating…