相关论文: Comments on Flipped SU(5) (and F-theory)
We investigate the unification constraints in the minimal sypersymmetric grand unified theories based on SU(5) gauge symmetry. The most general constraints on the spectrum of minimal supersymmetric SU(5) and flipped SU(5) are shown. The…
It is shown that by a simple extension of the fermion sector of flipped SU(5) models and other flipped models proton decay coming from dimension-6 operators can be suppressed by fermion mixing angles by an arbitrary amount in a natural way.
We study colored Higgsino-mediated proton decay (dimension-five proton decay) in a model based on the flipped $SU(5)$ GUT. In the model, the GUT-breaking ${\bf10}$, ${\bf \overline{10}}$ fields have a GUT-scale mass term and gain VEVs…
We review the main constraints on the parameter space of the minimal renormalizable supersymmetric SU(5) grand unified theory. They consist of the Higgs mass, proton decay, electroweak symmetry breaking and fermion masses. Superpartner…
We construct three flipped SU(5) X U(1)_X models from F-theory, and consider two such models from free fermionic string model building. To achieve the decoupling scenario in F-theory models and the string-scale gauge coupling unification in…
We embed the flipped SU(5) models into the SO(10) models. After the SO(10) gauge symmetry is broken down to the flipped SU(5) \times U(1)_X gauge symmetry, we can split the five/one-plets and ten-plets in the spinor \mathbf{16} and…
The supersymmetric flipped $SU(6)\times U(1)$ gauge symmetry can arise through compactification of the ten dimensional $E_8\times E_8$ superstring theory. We show how realistic phenomenology can emerge from this theory by supplementing it…
We present an account of the early developments that led to the present form of the flipped $SU(5)$ string model. We focus on the method used to decide on this particular string model, as well as the basic steps followed in constructing…
We present the supersymmetric $SU(5)$ models which provide a simple ``all order'' solution to the doublet-triplet splitting problem through the missing doublet mechanism. The crucial role is played by the anomalous $U(1)_A$ gauge symmetry…
The instability of protons is a crucial prediction of supersymmetric GUTs. We review the decay in minimal supersymmetric SU(5), which is dominated by dimension-five operators, and discuss the implications of the failure of Yukawa…
We are inspired by the facts that M-theory may reconcile the supersymmetric GUT scale with that of quantum gravity, and that it provides new avenues for low-energy supersymmetry breaking, to re-examine a flipped SU(5) model that has been…
Quantum gravity or string compactification can lead to effective dimension-5 operators in Grand Unified Theories which modify the gauge kinetic terms. We exhaustively discuss the group-theoretic nature of such operators for the popular…
Extensions of the standard model with low-energy supersymmetry generically allow baryon- and lepton-number violating operators of dimension four and five, yielding rapid proton decay. The dimension-four operators are usually forbidden by…
A generic feature of string-derived models is the appearance of an anomalous Abelian U(1)_A symmetry which, among other properties, constrains the Yukawa couplings and distinguishes the three families from each other. In this paper, we…
We discuss the first string theory examples of three generation non-supersymmetric SU(5) and {\em flipped} SU(5) GUTS, which break to the Standard model at low energy, without extra matter and/or gauge group factors. Our GUT examples are…
These lectures begin with a brief introduction to the minimal supersymmetric standard model (MSSM) and the various mechanisms for hidden sector supersymmetry breaking and go on to provide a pedagogical discussion of the various kinds of…
We study a very simple, yet potentially realistic renormalizable flipped SU(5) scenario in which the right-handed neutrino masses are generated at very high energies by means of a two-loop diagram similar to that identified by E. Witten in…
We analyze the possible magnitude of the supersymmetric contribution to $g_\mu - 2$ in a flipped SU(5) GUT model. Unlike other GUT models which are severely constrained by universality relations, in flipped SU(5) the U(1) gaugino mass and…
Recently we have proposed a renormalizable grand unified theory, based on the SU(5) gauge symmetry, where the neutrino masses are generated through the type I and type III seesaw mechanisms. In this letter we study the supersymmetric…
We investigate the low energy properties of an effective local model with flipped $SU(5)\times U(1)_{\chi}$ gauge group, constructed within the framework of F-theory. Its origin is traced back to the $SO(10)$ symmetry -- associated with a…