|MadSci Network: Physics|
Your scenario has too many unknowns to provide a specific answer. Assuming the person being rescued had to travel by more conventional methods (instantaneous travel was invented after the person left), there are still other possible explanation for still being alive. Perhaps, a century from now, the traveler had access to technologies enabling suspended animation. Use of a wormhole to rescue the traveler should allow a simple computation of the amount of time required to travel the distance in question. You can graph the time required as a function of the speed of the traveler; and, from that graph decide whether the time or energy required was such that it would be better to assume the traveler was on ice to slow aging. For the time required to travel a distance at relativistic speeds, consult a college level physics textbook, or one of the following references: - Walter Scheider, Maxwell's Conundrum: A serious but not ponderous book about Relativity, Cavendish Press, Ann Arbor, 2000, isbn 0-9676944-0-x - Ray Skinner, Relativity for Scientists and Engineers, Dover Publications, New York, 1982, isbn 0-486-64215-1 - Taylor and Wheeler, Spacetime Physics, W. H. Freeman and Company, San Francisco, 1966, isbn 0-7167-0314-9 Thanks for your question.
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