Novikov Windows by Chris Cosmain

In 1996, time traveler David Singh recruits a small group of experts to build a time machine using components sent from the future.
They soon learn a grim truth. Events of the past and future are unalterable and free will is an illusion. Travelling back in time without being able to change anything can pose an immeasurable psychological burden. This is a Novikov Window, being trapped in an unalterable sequence of events in the past. To avoid Novikov Windows, knowledge about the future is closely guarded, breeding suspicion and manipulation.
What begins as a thrilling scientific adventure takes a dark turn and the group is faced with increasingly difficult and unethical missions. Tensions rise, frayed by moral and ideological differences. Can they find hope in the face of impossible decisions, in a universe where there are no choices?