Strong rec for Greg Egan’s Clockwork Rocket series, which explores the role of the +++- metric tensor in chronology protection in our universe, by contrasting i

Strong rec for Greg Egan’s Clockwork Rocket series, which explores the role of the +++- metric tensor in chronology protection in our universe, by contrasting it with a universe with a ++++ metric tensor. As per his style, it’s a fiction book set in a universe with these different physical rules, as the characters work out the consequents (and consequences) of these rules, which of course have been thoroughly worked out by the author. It’s a weird genre of fiction in that parts of it are basically unreadable if you don’t have a physics education. Egan seems to fall in the camp that A) the direction of time might be a purely cosmological phenomenon rather than a local one and B) time paradoxes in a universe that admits causal loops can possibly be resolved by just making them unlikely. His pitch is fairly compelling.