【英语时差8,16】时间之谜--时间能倒流吗?（在线收听）

Some scientists say time is governed by the movement of matter in our universe. They say time flows forward because the universe is expanding. Some say it will stop expanding some day and will begin to move in the opposite direction, to grow smaller. Some believe time will also begin to flow in the opposite direction -- from the future to the past. Can time move backward? Most people have no trouble agreeing that time moves forward. We see people born and then grow old. We remember the past, but we do not know the future. Some scientists believe there is one reason why time only moves forward. It is a well-known scientific law -- the second law of thermodynamics. That law says disorder increases with time. In fact, there are more conditions of disorder than of order. For example, there are many ways a glass can break into pieces. That is disorder. But there is only one way the broken pieces can be organized to make a glass. That is order. If time moved backward, the broken pieces could come together in a great many ways. Only one of these many ways, however, would re-form the glass. It is almost impossible to believe this would happen. Not all scientists believe time is governed by the second law of thermodynamics. The debate will continue about the nature of time. And time will remain a mystery.