Peter Kagey in a Rhombic Dodecahedron made from Truncated Octahedra

Hello! I’m Peter!

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Saved video tweets (Part 3/4)
As I discussed in Part 1 and Part 2, I’m going through my old saved tweets and documenting them as I move to Bluesky (@peterkagey.bsky.social). Here are four (secretly five!) of those tweets (all of which had video/GIF embeddings):
- Rafael Araujo with geometric art (2023-09-30)
- Keishiro Ueki’s hinged objects (2023-11-02)
- Amy Goodchild illustrating Genuary 2024 (2024-01-01)
- Matt Pritchard with an optical illusion (2024-02-17)
Rafael Araujo with geometric art

I think this could be an interesting problem to have multivariable calculus students model. Here’s my attempt:

Here’s the quick and dirty Mathematica code:
```
colors = {RGBColor["#a476b9"], RGBColor["#4476bc"], RGBColor["#73b9a3"], RGBColor["#faf0e1"], RGBColor["#fbe5cc"], RGBColor["#e85981"], RGBColor["#f3c0ee"], RGBColor["#d3cdd6"]};
c=4; a=0.35;
fs:=Table[
    {Cos[-t],2Sin[-t]}+a*{Cos[-c*t+s],Sin[-c*t+s]},
    {s,0,2\[Pi]-(2\[Pi])/8,(2\[Pi])/8}
];
frames=Table[
    ParametricPlot[
        fs,{t,-\[Pi]/4,tf},
        Background->Black, PlotRange->{{-2,2},{-3,2}}, Axes->False,
        PlotStyle->({JoinForm["Round"],CapForm["Round"],Thickness[0.02],#}&/@colors)
    ],
    {tf,-\[Pi]/4+0.01,2\[Pi]-3\[Pi]/4,0.05}
];
Export[NotebookDirectory[] <> "geometric_paint.mp4", frames]
```
Keishiro Ueki’s hinged objects

Keishiro Ueki is on Bluesky as @keishiroueki.bsky.social. The first video is a minute long and has twelve (!!) examples—each of them very slick!

This next video reminds me of Martin Schwab’s “Mechanized Hinged Truchet Tiling,” which you can see on Mathstodon! (You won’t regret clicking on the link!)

Amy Goodchild illustrating Genuary 2024

Amy is at Bluesky with the handle @amygoodchild.bsky.social.

I find this “Genuary Day 1” post to be both very pretty and very inspiring.

Matt Pritchard with an optical illusion

Matt Pritchard is on Blueksky as @sciencemagician.bsky.social. The illusion is closely related to the Ames illusion; the gridlines are not parallel!
Saved video tweets (Part 2/4)
As I discussed in Part 1, I’m going through my old saved tweets and documenting them as I move to Bluesky (@peterkagey.bsky.social). Here are four of those tweets (all of which had video/GIF embeddings):
- Matt Henderson on triangle center fractal (2020-06-05)
- Josh Millard on woodworking by Olivier Gomis (2021-03-30)
- Pierre Thibault topology animation (2021-12-17)
- Flávio Costa on pen plotting to music (2023-04-23)
Matt Henderson on triangle center fractal

I didn’t know it at the time, but this Tweet would become the basis of some exciting mathematical explorations for me. See my blog post “Triangle center patterns” to read more about the journey this tweet took me on. (Matt Henderson is now on Bluesky as @matthen.com.)

This tweet became the basis of Problem 129 of my Open Problem Collection, and resulted in the creation of my video “Triangle Center Fractals” being chosen for the Mathematical Art Exhibition at the 2024 Joint Mathematics Meeting.

Josh Millard on woodworking by Olivier Gomis

Josh Millard links to a video showing a gorgeous bit of woodworking from the 26-year-old woodworker Olivier Gomis. (Josh is now on Bluesky as @joshmillard.bsky.social.)

At the time of this blog post, it appears you can buy this for $770.

Pierre Thibault topology animation

I feel like I could watch this two second loop a countably infinite number of times. (Pierre Thibault is now on Bluesky as @pierrexthibault.bsky.social.)

Flávio Costa on pen plotting to music

Sound on!

Video by Duncan Lockerby (@axidrawn on Instagram).
Saved video tweets (Part 1/4)
As I discussed previously, I’m going through my old saved tweets and documenting them as I move to Bluesky (@peterkagey.bsky.social). Here are four of those tweets (all of which had video/GIF embeddings):
- Peter Huxford on a cubic curve determined by 9 points (2020-11-12)
- Vincent Pantaloni on folding a dodecahedron (2020-11-11)
- Paula Beardell Krieg on “Rolling Oloid” (2020-10-24)
- Rob on building LEGO at the Tate Modern (2019-08-09)
Peter Huxford on a cubic curve determined by 9 points

I posted about this demo on Bluesky. My guess is that it is in response to a post that was drawing conic sections through five points.

I’d like to see an applet that shows an analogous setup for an algebraic curve of arbitrary degree \(n\) that is described by \(\binom{n+2}{2}-1\) points in the plane. (Let me know if you know about one!)

Play around with the demo yourself on on a (hacked version) of Desmos hosted on Peter Huxford’s academic website.

Vincent Pantaloni on folding a dodecahedron

This demonstration takes two dodecahedral half-nets and a rubber band, and *pop* turns it into a dodecahedron with a geodesic going around it—no glue or tape required!

Paula Beardell Krieg on “Rolling Oloid”

Some of my favorite saved tweets are the ones that I have a different perspective on now than I had when I first saved it. In particular, this demo suggested by Juan Carlos (@jcponcemath.bsky.social) and Paula Beardell Krieg (@paulakrieg.bsky.social) now reminds me of a project my students did in the “Making Mathematics” topics class that I taught at Harvey Mudd College in Spring 2024. Check out the link to my students’ blog post below.

See the Geogebra demo, where you can change the camera angle.

And here’s the link to my students’ project that I had promised in the lede. (The students gave the art to me as a gift, and I now have it in my office at Cal Poly Pomona!)

Sphericoin Art

Rob on building LEGO at the Tate Modern

This is Olafur Eliasson’s “The cubic structural evolution project”, 2004 at the Tate Modern.

I first learned about this artist when my wife took me to Olafur Eliasson: OPEN at The Geffen Contemporary at MOCA a few months ago, just a few stops south of our house along the A Line Metro.

As an example of my own experience with the Baader-Meinhof phenomenon, I recently Olafur Eliasson appear in the article “The Space Club Invasion” about a indoor playplace in Brooklyn for Instagram parents on Curbed, which you should read!

Space Club is a phenomenon in itself — half McDonald’s PlayPlace, half Olafur Eliasson installation, built for selfie-ing parents as much as their children.
“The Space Club Invasion”