Two sculptures beside the beautiful canal bridge at Broombridge, in memory of the day in 1843 that 38-year-old William Rowan Hamilton, walking with his wife Helen, scratched the recipe for quaternions into the stone of the bridge in case he'd forget it later
#Quaternions #RowanHamilton #Broombridge
Visualizing quaternions | Ben Eater

Explaining how quaternions, a four-dimensional number system, describe 3d rotation.

Reworked the 24-cell sketch, much easier to understand now.

Every one of the 12 visible #spinors has a button that brings the yellow spinor (the 1 state) to the clicked one because in 3D spinors double as rotations. (both are #quaternions so there exists a quotient between spinors, which is a rotation).

I think what's clear is that thinking in terms of a spinorial/rotational lattice makes things much easier to grasp than in terms of a vectorial/translational lattice

https://editor.p5js.org/aap/sketches/-N-Bnk_jn

This article by Simon Altman on #quaternions and rotations may be the most lucid i've seen on the topic: https://worrydream.com/refs/Altmann_1989_-_Hamilton,_Rodrigues,_and_the_Quaternion_Scandal.pdf

My beloved #spinors are also mentioned. It is rarely explicitly stressed that the quaternionic imaginaries are 180° rotations, not 90° rotations. The same *can* be said of the complex numbers too of course, but commutativity makes things special there.

ah yes. #quaternions and #euler .
Of course. I should have known, right ?
 

( I wonder what #Euler would think if I used their lifework, to pose cute 3D Models to server for #Fanart   )

#MikuMikuDance

@enigmatico would love this. As it involves loooooots of #math .

P.S.
I couldn't work out in my head what would be an appropriate order in which to enumerate the vertices of a four-dimensional hypercube given e.g. by
α+βi+γj+δk
where each of the Greek letters is 0 or 1.

#FourDimensional
#Quaternions

Project complete!

https://quaternion.cafe/ is a "vim-style" interactive tutorial that teaches sensor fusion with quaternions. It's mostly an aggregation of stuff I learned over the past few years while messing with inertial sensors.

#hardware #math #quaternions

An interactive guide to sensor fusion with quaternions

Learn how to incorporate quaternions in your next hardware project with interactive 3D visualizations and real sensor data.

I was up until 2am last night working on this. Whoops! I implemented a basic real-time code-editor and the visualizations. It uses the Intersection Observer API to only play the canvas when the visualization is in the browser viewport (kinda nifty!). #javascript #quaternions #math