Nature Loves Symmetry

From snowflakes to starfish to the DNA double helix, symmetry is the default aesthetic of nature. It is also the deepest principle of modern physics, the thread tying together everything in this lesson — from conservation laws to the particles in the Standard Model.

Symmetric bridges and domes spread their loads evenly. Symmetric error-correcting codes catch and repair mistakes in nearly every data transmission. And a little asymmetry is just as vital: the slight imbalance after the Big Bang is what let galaxies, planets, and you exist at all.