And, being he described as an infinity of indivisible particles, which he dubbed atoms from the Greek.

他将原子描述为无限的极微小的,粒子，他用德语给原子命名。

麻省理工公开课 - 固态化学导论课程节选

And it turns out the second solution, with negative energy, was when the theory is telling you, hey, there are particles and there are anti-particles, and the negative energy when properly interpreted will describe anti-particles.

结果,后来证明,第二个根,也就是能量为负的那个根,正是理论的关键,世界上既有粒子,也有反粒子,负能量就是用来解释反粒子的

耶鲁公开课 - 基础物理课程节选

It's a particle of mass m and momentum p has this energy so you solve for the energy, you get two answers.

一个质量为m,动量为p的粒子,有这么大的能量,你解出能量,得到两个解

耶鲁公开课 - 基础物理课程节选