In a mind-bending story with vast ideas on every page bang, the artificial intelligence Ulixes-316 starts as a financial agent for a galaxy-spanning bank in which he and Poluphemos witness (or cause?) an explosion that sets off a wavefront that’s collapsing space time at an ever expanding rate. With this as background, time travel plays both a minor role in a light-years-wide tachyon-based computing network and the key role in how a degenerating Ulixes can take care of his damaged companion Poluphemos and take an ethically questionable step that involves rewriting the Big Bang.
Correct, little algorithm, but we are not in your present. We transmitted ourselves by tachyons into the past, back into the stelliferous period, to one of the first galaxies. We have been working here in the morning of the Universe for twelve million years.

Variants

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  1. “Flight from the Ages” by Derek Künsken, in Asimov’s Science Fiction, May/June 2016.
    2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Derek Künsken