The only other direction involving the Higgs fields and thus soft terms of the order of µ is H$_{u}$H$_{d}$ . The rest are purely leptonic, such as LLe , or baryonic, such as udd , or mixtures of leptons and baryons, such as QLd . These combinations give rise to several independent flat directions that can be obtained by permuting the flavor indices. For instance, LLe contains the directions L$_{1}$L$_{2}$e$_{3}$ , L$_{2}$L$_{3}$e$_{1}$ , and L$_{1}$L$_{3}$e$_{2}$ , let us consider a particular configuration [92]: L$_{1}$ = 1 √$_{3}$   φ 0   , L$_{2}$ = 1 √$_{3}$   0 $_{φ}$  , e$_{3}$ = 1 √$_{3}$ φ, (123) The SU(2) × U(1) D -terms are where g = e/ sin θ$_{w}$ is the SU(2) coupling and g ′ = e/ cos θ$_{w}$ is the U(1)$_{Y}$ coupling. When L 1 = L 2 = e$_{3}$ = φ the D -terms in the potential vanish as they must. V$_{D}$ = g 2 8 ( | L$_{1}$ | 2 − | L$_{2}$ | 2 ) 2 + g ′ 2 72 ( | L$_{1}$ | 2 − 3 | L$_{2}$ | 2 + 2 | e$_{3}$ | 2 ) $^{2}$, (124) Along a flat direction gauge symmetries get broken, with the gauge supermultiplets gain- ing mass by super-Higgs mechanism with m$_{g}$ = g 〈 φ 〉 . Several chiral supermultiplets typically become massive by virtue of Yukawa couplings in the superpotential; for example, in the LH$_{u}$ direction one finds the mass terms W$_{mass}$ = λ$_{u}$ 〈 φ 〉 Qu + λ$_{e}$ 〈 φ 〉 H$_{d}$e . In this respect when the flat direction VEV vanishes, i.e. φ = 0, the gauge symmetry gets enhanced. Vacuum degeneracy along a flat direction can be broken in two ways: by SUSY breaking, or by higher order non-renormalizable operators appearing in the effective low energy theory. Let us first consider the latter option. Non-renormalizable superpotential terms in the MSSM can be viewed as effective terms that arise after one integrates out fields with very large mass scales appearing in a more fundamental (say, string) theory. Here we do not concern ourselves with the possible restric- tions on the effective terms due to discrete symmetries present in the fundamental theory, but assume that all operators consistent with symmetries may arise. Thus in terms of the invariant operators X$_{m}$ , one can have terms of the type [325, 326] 1. Non-renormalizable superpotential corrections W = h dM d − $_{3}$X k m = h dM d − $_{3}$φ $^{d}$, (125) 57