What is a GUTship?

Answer 1

A GUTship (Grand Unified Theory) is a fictional space craft developed by British author Stephen Baxter.

It is described in Baxter's Xeelee series of books as providing propulsion by heating matter up to such high temperatures that the fundamental forces unify, thereby releasing huge amounts of energy. The GUTship Northern in the book "Ring" used a captured asteroid to provide propulsion material for its 1,000 year journey.

GUTships are relativistic craft - they travel at the speed of light (but no faster).