中微子和假想的引力子也是无质量粒子, 它们也以与光相同的速度运动.Neutrinos and the hypothetical gravitons, also massless particles, move at the same speed as light.在本文中, 只简单的讨论了在树图近似下引力子的相互作用势能.In this paper, the interactional potential energy of gravi...
骑自行车是一项不错的锻炼方式。它能使身体各部分的肌肉更强健。Cycling is good exercise. It strengthens all the muscles of the body.统一体总要分解为不同部分的.A unity invariably tends to break up into different parts.构成那部小说开头部分的几章特别好.The chapters that comprise the f...