Charge balance: G(e_aq⁻) − G(H₃O⁺) = 0 (identity under substitution)

Sympy-exact witness of the charge-conservation identity in water radiolysis. Setup: define G_bal(G_e, G_H3O) = G_e − G_H3O as the charge-imbalance functional. Conservation axiom: every primary ionization produces one e_aq⁻ and one H₃O⁺,…