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Mathematics

Representing Rotations with Quaternions

Quick fact

The quaternion formula was carved into a bridge in Dublin, Ireland, by its discoverer: 'i² = j² = k² = ijk = −1' – creating a mathematical breakthrough in 1843.

Why this is interesting

You've likely rotated objects in a video game or on your phone, but did you know that the elegant behind-the-scenes math uses four-dimensional numbers? Why do animators and engineers prefer these mysterious 'quaternions' over simpler seeming angles?