Joseph A. Zaki

The adventures of a group of explorers who make use of a newly discovered wormhole to surpass the limitations on human space travel and conquer the vast distances involved in an interstellar voyage.

Major Bill Cage is an officer who has never seen a day of combat when he is unceremoniously demoted and dropped into combat. Cage is killed within minutes, managing to take an alpha alien down with him. He awakens back at the beginning of the same day and is forced to fight and die again... and again - as physical contact with the alien has thrown him into a time loop.