Gravitationskraft

${\underset{\_}{F}}^{(12)}=-\gamma m_s^{(1)}{m}_s^{(2)}\frac{{\underset{\_}{r}}^{(1)}-{\underset{\_}{r}}^{(2)}}{{|{\underset{\_}{r}}^{(1)}-{\underset{\_}{r}}^{(2)}|}^3}$