Algebra: Feynman's Physics Explained

Feynman Vol I8-9

Mathematics is the language of physics and algebra is its grammar. Starting from simple counting and a few rules, we abstract them and demand they keep working even where the original meaning breaks down — which forces us to invent negative numbers, fractions, and finally complex numbers. The crowning result is Euler's formula, which reveals a stunning hidden link between exponential and trigonometric functions: they are two sides of the same coin.

The big idea

Pushing the rules of arithmetic to their limit reveals deep hidden unity.

Think about it

Why might mathematicians 'invent' a number for the square root of a negative — and why would physics ever need it?

← More Physics (Feynman Lectures) guides  ·  Explore the Physics (Feynman Lectures) module →

📧 Get a free brain-teaser every morning

Join thousands of families learning something new each day.

Subscribe free