The Lexman Spacedrive gave man the stars -- but at a fantastic price. Interstellar exploration, colonization, and trade became things of reality. The benefits to Earth were enormous. But because of the Fitzgerald Contraction, a man who shipped out to space could never live a normal life on Earth again.
Travelling at speeds close to that of light, spacemen lived at an accelerated pace. A nine-year trip to Alpha Centauri and back seemed to take only six weeks to men on a spaceship. When they returned, their friends and relatives had aged enormously in comparison, old customs had changed, even the language was different. Это и многое другое вы найдете в книге Starman's Quest (Robert Silverberg)