Albert Einstein was a famous physicist known for his theory of relativity E = mc².
School psychologist J. Loren Pryor had a poster of Einstein in his office at Springfield Elementary School.  Homer also once had a poster of Albert Einstein in his college dorm bedroom. Sideshow Bob was once going to steal Einstein's DNA from a museum to use to make himself smarter.
Non-canon Appearances Edit
Einstein once came back as a zombie after Bart read an incantation while trying to resurrect one of the deceased Snowball.. Einstein was envisioned in jew heaven dancing by Krusty after his father died. 
He also "appeared" in the Treehouse of Horror XVI segment "I've Grown a Costume on Your Face". A Witch turned everyone in Springfield into what or who their costumes represented. As Lisa was with an Albert Einsten costume, she became him. Later, she realized that Maggie was turned into a real witch and would be able to reverse the spell. 
- Episode – "Bart the Genius"
- THOH – "Treehouse of Horror III" (Zombie)
- Episode – "Separate Vocations"
- Episode – "Homer Goes to College"
- THOH – "Treehouse of Horror XVI" (I've Grown a Costume on Your Face, Portrayed by Lisa)
- Episode – "The Man Who Grew Too Much"
- Episode – "Clown in the Dumps" (Seen in jew heaven)