把以下文章翻译成英语。


很多人认为时光机只是科幻小说中的道具，但是存在一些科学理论表明时光旅行在理论上是可能的。其中一种理论是广义相对论。根据这个理论，如果我们能够制造一个没有质量、自旋和电荷的理论物质，那么在这个物质周围的时空可能会扭曲到一种特殊的方式，可以让时间穿越成为可能。
Many people believe that time machines are only props in science fiction, but there are scientific theories that indicate time travel is theoretically possible. One such theory is the theory of general relativity. According to this theory, if we could create a theoretical substance that has no mass, spin, or charge, the space-time around this substance could warp in a special way to make time travel possible.