Ring (The Xeelee Sequence #4) (Mass Market)
It worked. Too well.
Poole was never seen again. Then from far in the future, from a time so distant that the stars themselves were dying embers, came an urgent SOS--and a promise. The universe was doomed, but humankind was not. Poole had stumbled upon an immense artifact, light-years across, fabricated from the very string of the cosmos.
The universe had a door. And it was open...
Stephen Baxter is an acclaimed, multiple-award-winning author whose many books include the Xeelee Sequence series, the Time Odyssey trilogy (written with Arthur C. Clarke), and The Time Ships, a sequel to H. G. Wells's classic The Time Machine. He lives in England.