How many times you have read fiction strories which talks of two different worlds in different dimensions in the universe? But wait a minute, they arent different in all sense but in the time dimension. Everything is the same, but time. I have read hundreds of such stories and even a handful of science programs which talks of the same topic that "there may be another earth in this universe which is same in all aspects but the time there either lags behind of ours or they are in the future." Can this be possible or how it is actually explained?