A physicist's future me travels back in time to warn him about the perils of breaking up with Gwen.
His story was ridiculous, but he really did look like me plus twenty years, and he knew things about me that nobody else could know.

Variants

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  1. “Early Warnings” by Martin L. Shoemaker, in Analog, April 2016.
  2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Martin L. Shoemaker