Einstein's theory abolished the idea of absolute time and established that it is a plastic medium. He postulated that if you had a set of twins and one remained on Earth while the other was rocketed into outer space, they would experience time differently. Time stretches with acceleration, he said, so that the twin on the rocket would not age as fast as the twin left on Earth. Using special twin hydrogen maser clocks, one sent to space and one remaining on Earth, NASA eventually proved Einstein's theory. One of those clocks is on display.
Physicists believe time can behave in weird ways, especially intergalactically.
Out there, time apparently slows and even stops near black holes and bends around stars and other large objects. Others speculate that there are other times in other universes. But in the end, the experts really don't know much more about time than the average person on the street. All we know is most people don't have enough of it. Century African African American Ancient Antiques Architecture Asian Ceramics Contemporary Decorative Arts Early 20th Cent.