feynlag.vacuum.masses.charged_mass_matrix¶

feynlag.vacuum.masses.charged_mass_matrix(potential, vacuum, fields, tadpole_subs=None)[source]¶

Mass matrix of complex (charged) fields: ∂²V/∂φ̄ᵢ∂φⱼ.

Implements the DLRSM1 Dummy-conjugate trick: conjugate(φᵢ) is replaced by a Dummy, the derivative is taken with respect to the Dummies (rows) and the fields (columns), and the Dummies are restored before vacuum evaluation.