Gauge Coupling Unification inF-Theory Grand Unified Theories

Gauge Coupling Unification from Unified Theories in Higher Dimensions

A two-stage framework for unification is proposed involving grand unification, supersymmetry and extra dimensions, leading to a prediction for the strong gauge coupling, αKK s = 0.118±0.004±0.003, which is more successful and precise than that obtained from conventional supersymmetric grand unification, αSGUT s = 0.130 ± 0.004 ± ∆SGUT. Orbifold breaking of the unified gauge group leads to a non...

Supersymmetric Grand Unified Theories and Yukawa Unification

Merging gauge coupling constants without Grand Unification

The merging of the running couplings constants of the weak, strong, and electromagnetic fields does not require the unification of these gauge fields at high energy. It can, in fact, be the property of a general fermionic system in which gauge bosons are not fundamental. PACS 11.10.Hi, 12.10.Kt, 12.60.Re, 67.90.+z, 71.10.-w Email address: [email protected] Email address: ...

Grand Unified Theories

In spite of all the successes of the Standard Model [SM] it is unlikely to be the final theory. It leaves many unanswered questions. Why the local gauge interactions SU(3)C × SU(2)L × U(1)Y and why 3 families of quarks and leptons? Moreover why does one family consist of the states [Q, u, d; L, e] transforming as [(3, 2, 1/3), (3̄, 1,−4/3), (3̄, 1, 2/3); (1, 2,−1), (1, 1, 2)], where Q = (u, d) an...

Mirage gauge coupling unification

We use compact D = 4, N = 1, Type IIB orientifolds as a testing ground for recent ideas about precocious gauge coupling unification and a low energy string scale. We find that certain such orientifolds have the interesting property that gauge couplings receive moduli-dependent corrections which mimic the effect of field theoretical logarithmic running. The effective cut-off scale for the logari...