I recently read Greg Egan's previous trilogy set in an alternate-physics universe, the Orthogonal trilogy, and it was excellent. (In Orthogonal, time is a space

I recently read Greg Egan's previous trilogy set in an alternate-physics universe, the Orthogonal trilogy, and it was excellent. (In Orthogonal, time is a space-like dimension, and relativity, optics, and chemistry change accordingly.) Not only does Egan invent weird universes and let the reader follow the math involved to whatever extent they want, he also tells great stories in the universes he invents. Orthogonal tells of a society's quest through deep space, searching for a way to survive and save their home planet, using technology they have to invent along the way. (The characters can speak in diagrams, with which they explain the science to each other and to the reader.) It builds up to include some plot twists that are only made possible by the strange nature of time and space. Dichronauts seems to be an iteration on this formula (now there are two time-like dimensions), which sounds more bewildering and constraining to the plot, but I trust Egan to do it well.