现在还有奴隶吗?有,不仅有,还有大概三千万。根据澳洲一个组织(Walk Free Foundation),美国大概有六万,中国大概有三百万。 http://www.washingtonpost.com/blogs/worldviews/wp/2013/10/17/this-map-shows-where-the-worlds-30-million-slaves-live-there-are-60000-in-the-u-s/ We think of slavery as a prac ...
4 Reasons Why The EM Drive is Probably Bullshit 第一,它违反了经典力学的动量守恒原理。不喷射带质量的粒子,产生反作用力,如何产生推力? http://www.theskepticsguide.org/4-reasons-why-the-em-drive-is-probably-bullshit Bob Novella August 7, 2014 ...