Related Clues:

• Genius
• Brainiac
• Source of the quote
• Unit of force
• See 42-Down
• See 58-Across
• A genius, relatively speaking
• See 18-Across
• Mastermind
• See 47-Down
• Law of gravity formulator
• Gravity beholder
• Force unit
• Noted mathematician
• See 12-Across