"The Answer" by H. Beam Piper is a science fiction short story published in 1959. Fifteen years after a devastating nuclear war between the United States and Soviet Union, two scientists in Argentina conduct an experiment with negamatter that produces an unexpected result. The explosion's distinctive signature leads one scientist to a stunning realization about what truly triggered the catastrophic war that destroyed the Northern Hemisphere—a discovery that changes everything they thought they knew. (This is an automatically generated summary.)