科学探秘：人们有穿越时空的可能吗？

你有梦想过穿越时空吗？其实它也没有你想象的那么不可能。

事实上，我们中的大多数人已经在生活中穿越过时空。难以置信是吗？结果就是我们可能比自己想的要年轻。一起来看看科学家的说法吧。

Have you ever wished you could travel through time? Well, it's not as far-fetched as you might think. The reality is, most of us have already traveled through time in our daily lives, and that we may be somewhat younger than we think as a result. According to Albert Einstein's special theory of relativity, our perceptions of time and space are defined by motion and speed. In other words, time actually moves slower for someone travelling in higher speeds, relatively someone standing still. So believe it or not, every time you take a flight on an airplane, you actually jump a tiny fraction of a second into the future. In fact, it's called time dilation. And as you fly, the more pronounced the time shift would be.

Scientists set out to prove this theory in 1971 by loading an atomic clock on the jet and sending it around the planet at five hundred miles an hour. Another atomic clock was kept at the airport. Surprisingly, when the jet returned, the clock on the plane that essentially registered the time was 16 nano seconds earlier than the one left on the ground. Now you'd have to be traveling extremely fast for there to be any real significant time shift. Even at the spatial rocket in the space at seventeen thousand miles an hour for a full year. The crew would still only jump amazingly 3.8 seconds into the future.

So, why don't we just build machines that can go a lot faster than that? First, the speed needed for a dramatic time jump is far beyond our current technology. And second, the Laws of Physics say it's impossible to travel that fast. To make a really significant time jump, we need to travel faster than the speed of light over 186 thousand miles a second, which scientists say it's impossible. But then again, we thought no one could surpass the speed of sound until Chuck Yeager did it in the late 1940s.

If we could eventually break the light barrier, scientists believe that some really strange things might start to happen. First, as we approach the speed of light, it's believed we will jump further and further into the future. By then, once we surpass the speed of light. Some scientists think we might actually start going backwards in time. Everything would appear to go in reverse. Skeptics believe strange time travel theories like these are preposterous. 'Coz the Laws of Physics will never allow us to approach and surpass the speed of light. But Chuck Yeager once proved skeptics have been wrong before.