Matthew Broderick
Richard Feynman
Patricia Arquette
Arline Greenbaum
Peter Riegert
Mel Feynman
Raffi Di Blasio
Robert
Josh Keaton
David
James Hong
Abacus Adder
Peter Michael Goetz
Dr. Gell-Mann
Kelly Wolf
Nurse Kate
Mary Pat Gleason
County Nurse #2
Joyce Van Patten
Aunt Ruth
James Le Gros
John Wheeler
Zeljko Ivanek
Bill Price
Joshua Malina
Calculator Kid #3
Matt Mulhern
Gate Guard
Jeffrey Force
Young Richard
David Drew Gallagher
Harold
Melissa DeLizia
Young Joan