20180906 USA VISUALIZING QUATERNIONS 3BLUE1BROWN

Frames from "Visualizing quaternions (4d numbers) with stereographic projection," the interactive video and accompanying explorable web page Grant Sanderson (who runs the math-education YouTube channel 3Blue1Brown) made jointly with the programmer-educator Ben Eater, published 6 September 2018. The piece unfolds the quaternion unit sphere via stereographic projection into flat space, letting a viewer drag through 4D rotations and watch their 3D shadow, widely regarded as one of the clearest public explanations of quaternions ever produced.

The card

• Date — 6 September 2018
• Where — 3Blue1Brown (Grant Sanderson) and Ben Eater, joint interactive video project; digital publication, no physical findspot. No coordinates are given on the map for this reason.
• Evidence grade — WEB-PHOTO
• Photo credit — Grant Sanderson (3Blue1Brown) and Ben Eater

Sources

• eater.net
• 3blue1brown.com

Works Cited

• Source, Title, Publisher, Year.