In modern physics, the laws of conservation of momentum, energy, and angular momentum are of more general validity than Newton's laws, since they apply to both light and matter, and to both classical and non-classical physics.
Di fisika modern, hukum kekekalan dari momentum, energi, dan momentum sudut berlaku lebih umum daripada hukum-hukum Newton, karena mereka berlaku pada cahaya maupun materi, dan juga pada fisika klasik maupun fisika non-klasik.