Rohrlich Fritz
Syracuse University, Syracuse, New York 13244-1130, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2008 Apr;77(4 Pt 2):046609. doi: 10.1103/PhysRevE.77.046609. Epub 2008 Apr 29.
Using physical arguments, I derive the physically correct equations of motion for a classical charged particle from the Lorentz-Abraham-Dirac equations (LAD) which are well known to be physically incorrect. Since a charged particle can classically not be a point particle because of the Coulomb field divergence, my derivation allows for that by imposing a basic condition on the external force. That condition ensures that the particle's finite size charge distribution appears as a point charge to the external force. Finite radius charge distributions are known not to lead to differential equations of motion. The present work is in agreement with the results by [H. Spohn, Europhys. Lett. 50, 287 (2000)] and by others. An example, uniform acceleration, demonstrates what the above basic condition entails. For clarity of the argument, I discuss the nonrelativistic case before the relativistic one.
通过物理论证，我从洛伦兹 - 亚伯拉罕 - 狄拉克方程（LAD）推导出了经典带电粒子的正确运动方程，而众所周知，LAD方程在物理上是不正确的。由于库仑场发散，经典的带电粒子不能是点粒子，我的推导通过对外力施加一个基本条件来考虑这一点。该条件确保粒子的有限尺寸电荷分布对外力而言表现为点电荷。已知有限半径的电荷分布不会导致运动的微分方程。本工作与[H. Spohn，《欧洲物理快报》50, 287 (2000)]及其他作者的结果一致。一个例子，即匀加速，展示了上述基本条件的含义。为了论证清晰，我先讨论非相对论情形，再讨论相对论情形。
