Symmetry in Physical Laws: Feynman's Physics Explained

Feynman Vol I8-9

There is a deep, beautiful link between the symmetries of the universe and its conservation laws. Because the laws are the same everywhere (symmetry under moving in space), momentum is conserved. Because they do not change over time, energy is conserved. Because there is no special direction in space, angular momentum is conserved. For every symmetry of Nature, there is a matching conserved quantity.

The big idea

Every symmetry of Nature hides a conservation law.

Think about it

Conservation of energy comes from the laws not changing over time. What does that suggest about why energy is conserved?

← 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