Theorem: Delta t at v_GW = c equals 0 (GW170817 multi-messenger achromaticity)

Theorem (achromaticity-vGW-c canonical): substituting v_GW = c into Delta t = D(1/v_GW - 1/c) gives D(1/c - 1/c) = 0 identically. Canonical sympy pins: D, v_GW, c = sp.symbols('D v_GW c_var', positive=True); delta_t = D*(1/v_GW - 1/c);…