by David Garofalo
Twins are born at t > 0 according to the clock in the hospital room of a hospital situated in a one dimensional city within a one dimensional state on a planet located on the outskirts of a one dimensional galaxy. The address is x > 0. The birth is labeled by the doctors as event A. They work in a narrow building with exit doors both on the left and on the right. The twins, one green, the other blue, never get along. Their distaste for each other is marked by their birth. To most effectively push each other away, their doctor prescribes momentum conservation to ensure they never see each other again.
The twins remain attached to the doctor who delivered them and successfully keep in touch at regular intervals of time. Because the doctor works long hours, she lives for the most part on a vertical path, with only slight deviations left and right depending on whether she goes shopping, to a restaurant, or back home. The messages she receives from the twins suggest to her that both are simultaneously thriving, but not everyone agrees. The twins retain affection for their father despite the fact that even before the time of their birth, he was already miles away on the right, on an accelerated purple path that would take him as far from the twins as possible. They send the same information to their father who receives them via the blue and green signals at events B and C, as they do to their doctor.
Their communication is about to be hampered by a dark object lurking on the horizon, intent on absorbing all information. This object is created by the father and his right to view the world from his own perspective. Because he is forced to live at least partly in the real world, he travels slower than light, and the blue and green light messages catch up with him at least initially, although not at regular intervals as they do for the doctor. The messages from the blue twin arrive after increasingly long intervals and the images he receives seem to suggest that progress in life has slowed down dramatically and practically stalled. Blue twin appears to be falling into a bottomless pit. The father is sorry about this but has hope that all this will soon evaporate. From the father’s perspective, communication with blue twin ends at the dashed red line, after which no further events are registered, and the last nugget of information from blue twin arrives 50 years after birth and shows blue twin to be 25 years old. Green twin continues to update dad with more recent images and dad concludes that blue twin is in a middle age crisis.
Eventually dad tires of running away from his problems and settles down to a simpler life on a vertical path, and to his delight begins getting regularly timed messages from both twins, indicating both have resumed their lives and are doing well, and realizes that his impressions had little to do with the experiences of the twins. His worries and the event horizon both evaporate as all ends well.