Twin paradox for a realistically accelerating space travel


  • Pszota Gábor Miskolci Egyetem
  • Majár János Miskolci Egyetem



special relativity, twin paradox, time dilation, interstellar travel


A common example for Einstein’s special relativity [1] is the different aging of the twins, one of whom embarks on an interstellar journey. This problem was originally discussed with a spaceship moving at a constant speed there and back, and there was no mention of the accelerating interval. Without that, this situation appears to be paradoxical, since one can argue that the traveling twin also sees the other one moving, therefore the situation is symmetric. No such symmetry is apparent, however, if the interval of acceleration is considered, no matter how short that is [2,3]. We wanted to analyse this situation for a realistic scenario, where the spaceship would have a continuous acceleration and de-celeration of 1 g during the entire round trip. We present detailed calculations and an analysis of the aging difference for journeys to various distances and for various times.