令人兴奋的硬球
Exciting Hard Spheres
摘要：
本文研究了单个运动粒子入射到静止硬球气体中所产生的碰撞级联。我们认为，在时间t运动的粒子数随t^{xi}增长，到时间t为止的碰撞数随t^{eta}增长，其中xi=2d/（d+2），eta=2（d+1）/（d+2），d是空间维度。这些增长规律与爆炸产生的冲击波的流体力学理论中的增长规律相同。在d=1和2的情况下，我们的预测得到了分子动力学模拟的验证.对于一个粒子入射到半空间中的静态气体上，所产生的回溅最终包含了几乎所有的初始能量。
英文摘要：
We investigate the collision cascade that is generated by a single moving incident particle on a static hard-sphere gas. We argue that the number of moving particles at time t grows as t^{xi} and the number collisions up to time t grows as t^{eta}, with xi=2d/(d+2) and eta=2(d+1)/(d+2) and d the spatial dimension. These growth laws are the same as those from a hydrodynamic theory for the shock wave emanating from an explosion. Our predictions are verified by molecular dynamics simulations in d=1 and 2. For a particle incident on a static gas in a half-space, the resulting backsplatter ultimately contains almost all the initial energy.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
