Short Story
Grandpa?
- by Edward M. Lerner
- in Analog, July/August 2001
Professor Thaddeus Fitch gives a practical demonstration of the grandfather paradox to his physics classes.
Imagine that I had the technology with which to visit my grandfather in his youth. Once there, what is to stop me from killing him before he’d had the opportunity to reproduce? But if I did succeed, who was it who had travelled backward. . .