A clever idea, well handled.
Life in an underground city, hiding from nuclear winter on Earth. Or a 95% success rate journey through a wormhole to (alien) pastures new…. worth the risk??
A clever way to construct a story, and the characters are well-drawn.
Echoing an oriental fable, a scientist must head back in time, or, rather, experience time in reverse, until he is able to pluck his wife, stranded in a loop, into a time-stream that does not see here in a coma.
The title refers to the ancient question : if a ship has its planking replaced plank by plank over a period of years, when does it become a new ship? How does this applies this to humanity?
A strong issue, with stories from authors well-established and authors on the way up : Aliette de Bodard, Bruce McAllister, Caroline M. Yoachim, Damien Broderick, David Erik Nelson, Stephen Baxter.
Low on tech, high on humanity, an excellent Asimovs debut. (And ruminations on Avatar and The War Horse).