Many science-fictional ideas from the past have subsequently became scientific realities. Take space exploration, for example. In the 1950s this was just a fantastical idea that few people would have dreamt could actually happen. Now it's such a part of modern life that the latest blastoff of a spacecraft, or the discovery of a new planet often doesn't even make the national news.
以前科学小说中提出的很多想法已经变成了科学的现实。拿太空探险来说，50年代，这只不过是一种科学狂想，很少人相信有一天会变成现实。可是现在它已成为现代生活的一个组成部分，以至于一次最新的宇航器发射或者一个新行星的发现已不再列为国内新闻。
You cannot change the laws of physics ... but could physics actually enable us to travel through time? It might sound crazy, but according to Einstein's theories, there's no logical reason why time travel isn't possible and there are now scientists looking into it as a serious scientific proposal, at least at a theoretical level.
你无法改变物理学定律……但是物理学能否使我们在时间中旅行呢?这听上去或许像个痴想。但是根据爱因斯坦的理论，时间旅行在逻辑上不是不可能的。现在科学家正把它视为一个严肃的科学命题，至少在理论上如此。
