def jacobianDet (df_rho_drho df_T_dT df_rho_dT df_T_drho : ℝ) : ℝ := df_rho_drho * df_T_dT - df_rho_dT * df_T_drho
thesis/CESProofs/Dynamics/CoupledRhoT.lean:33
Coupled (ρ, T) Jacobian Analysis