Secretary of Defense Robert Gates said that while no one expects the world will achieve the goal of "zero nuclear weapons" anytime soon, the new treaty is a major step toward greater security with fewer nuclear weapons: "It is clear that we can accomplish goals with fewer nuclear weapons."

VOA: standard.2010.03.26

Pages and pages of them, so no one expects you to know all those identities, but there are a few popular ones we will use.

好几页的内容,我不要求你们都能记下来,但是我们会用到一些著名的恒等式

耶鲁公开课 - 基础物理课程节选