Finch, Sheila. "Old Man and C"
Divergence: c 1900 CE
What if: A Swiss patent office employee quit his job to become a professional musician.
Summary: As the USA drops a new type of bomb in Korea, a 75-year-old Albert Einstein frets about whether he's wasted his life as a violin teacher.
Published: In Amazing Stories, November 1989; and What Might Have Been? Volume 2: Alternate Heroes (eds. Gregory Benford and Martin H. Greenberg), q.v.