Twin Paradox

Register to read the introduction… According to the argument, twins (obviously of the same initial age) are on Earth. One boards a spaceship and travels close to the speed of light into space, turns around, and returns. When she returns, the twin who traveled is younger than her sibling because time slows as one approaches the speed of light. Carl Sagan explains: “‘[H]ere we have two identical twins who may be decades apart in age;’”4 however, besides the seeming-incongruity of twins of different ages, this “paradox” shows no real inconsistency in the possibility of time travel. Another paradox is the Grandfather Paradox: what if you could go back in time and kill your grandparents before your parents were conceived? Kip Thorne says, “Relativity theory says in general that once you’ve made a time machine you can never use it to go backward in time before the period when it was made.”4 A child born after the creation of the machine could prevent his own birth, however, so the paradox still exists. One theory that prevents this paradox, Hawking’s “Chronology Protection Conjecture,” says that “the laws of physics conspire to prevent time travel, on a macroscopic scale.”1 Another theory says that if you go back in time to murder your grandfather, you change the history in another, parallel universe in which you are never born; you do not affect history in your own universe, where you are born at the appropriate …show more content…
It is even more difficult to imagine the consequences that time travel would have on society. Currently, science has no real knowledge of the possibility of time travel. However, there is far more science behind time travel than most people realize. All humans are ‘stuck’ in the flow of time.3 Time travel would introduce a completely new perspective on time in which it could be possible to know past and future moments as surely as we can know the present. The past would no longer be irreversible and the future would no longer be inevitable. However, there are a few problems with this. Several theories exist about the possibility of changing the past, but the “Grandfather Paradox” best illustrates the logical problems with changing the past. Time travel into the indefinite future is far more possible because time actually slows as you approach the speed of light. The “Twin Paradox” illustrates the possibility that one twin could go on a space voyage and return to Earth only slightly older while his twin has long since died of old age. The consequences of time travel on society would be tremendous. Today’s moral systems are based on the concept that (as Shakespeare wrote) “what’s done cannot be undone.” A society in which the correction of past mistakes or the prevention of future ones was possible would most likely have a radically different moral system less focused on the consequences of one’s