For one $SU(3)$ triplet and no gauge multiplet, the only nonzero $G$-invariant soft term is the universal scalar mass,
$$
\mathcal L_{\rm soft}=-m_s^2\sum_{i=1}^3\phi_i^*\phi_i.
$$
An invariant bilinear does not exist, and the formal trilinear $A\epsilon^{ijk}\phi_i\phi_j\phi_k$ vanishes because the scalar fields commute. Thus the phrase “general soft terms” does not generate further interactions for the field content stated in the question.

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Solution

Past exam of the mathematics course of the University of Cambridge / 2026 / iii / Paper 307 / 1 / v / Solution

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ID: past-exam-of-the-mathematics-course-of-the-university-of-cambridge/2026/iii/paper-307/1/v/solution