To the outside world, Arthur was a success. He understood the language of the universe. But to Arthur, that language felt like a broken mosaic. To describe a rotating electron, he needed complex numbers. To describe its movement through space, he used vectors. To reconcile it with relativity, he turned to four-vectors and Pauli matrices.
He walked out into the crisp morning air of the campus. He saw a bird bank into a turn. To his old self, that was a change in a velocity vector. To his new eyes, it was a acting upon a multivector, a seamless transformation where geometry and algebra were no longer two things, but one. Geometric Algebra for Physicists
As the sun dipped below the horizon, Arthur’s chalk began to fly. He realized that by simply adding these different types of objects together—scalars, vectors, and bivectors—he created a . This was the "Geometric Algebra" Clifford had dreamed of. Suddenly, the "imaginary" To the outside world, Arthur was a success
By dawn, Arthur looked at his chalkboard. It no longer looked like a battlefield of indices. It looked like a map. He realized that for a century, physicists had been like builders trying to describe a house using only the lengths of the boards, ignoring the angles at which they met. Geometric Algebra provided the angles. To describe a rotating electron, he needed complex numbers