“…However, almost all the (classical) flat directions are quantum-mechanically unstable and lifted because a monopoleinstanton could generate a runaway potential for the Coulomb branch [16,17,36]. In so(N) gauge theories, only a few directions are non-perturbatively allowed and become exactly flat [26,27,[37][38][39]. In the present case, there is a single flat direction: The electric Coulomb branch operator, which is denoted by Y SO (5) , corresponds to the spontaneous gauge symmetry breaking [40][41][42] so (7) → so(5) × u (1) (2.1)…”