SOLVED. Science fiction. [s]

[Yossi]

Read this book in 1989. About a soldier who has to go through a tiny portal to a planet settled by survivors of a science experiment gone wrong.

The experiment was to test the technology for the portal on a large scale and resulted in an explosion that wiped out a large part of the united states and was mistaken for an a nuclear(?) first strike.

This soldier was chosen because of his experience being killed and resurrected repeatedly. Because the portal is so small, he has to be surgically sliced up and "die" first to pass through. He is joined by a female empath. Together they are transported through the portal to a regeneration tank where they are "grown" back into consciousness.

[Ayshe]

Is it The Space Eater?

[Yossi]

Yes!!! Thank you so much. This has been troubling me for the last 18 months...