About RobertLovesPi

I go by RobertLovesPi on-line, and am interested in many things, a large portion of which are geometrical. Welcome to my own little slice of the Internet. The viewpoints and opinions expressed on this website are my own. They should not be confused with those of my employer, nor any other organization, nor institution, of any kind.

Three-Legged Racer

Image

three_legged_racer

How America Typically Sees the World

Posted on 24 September 2016 by RobertLovesPi

how-america-sees-the-world

This problem reaches its worst levels during presidential campaign years. It’s particularly bad during 2016.

Building a “Polyhedral Porcupine”

Posted on 24 September 2016 by RobertLovesPi

This is the icosahedron, followed by its first stellation.

The first stellation of the icosahedron can be stellated again, and again, and so on. The “final stellation” of the icosahedron is the one right before the stellation-series “wraps around,” back to where it started:

This final stellation of the icosahedron would serve pretty well as a “polyhedral porcupine,” but I was seeking something even better, so I turned my attention to polyhedral compounds. This is the compound of five icosahedra:

The program I use to manipulate these solids is called Stella 4d: Polyhedron Navigator (free trial download available here). My next move, using Stella, was to create the final stellation of this five-icosahedron compound . . . and, when I saw it, I knew I had found my “polyhedral porcupine.”

A Rhombic Cage

Posted on 20 September 2016 by RobertLovesPi

rhombic-cage

This cage is made of 36 identical rhombi, and has six openings. I made it with Stella 4d, a program available at this website.

A Faceted Great Rhombcuboctahedron

Posted on 17 September 2016 by RobertLovesPi

faceted-trunc-cubocta

Some prefer to call the great rhombcuboctahedron the “truncated cuboctahedron,” instead. Whichever term you prefer, this is a faceted version of that Archimedean solid. I made it using Stella 4d: Polyhedron Navigator, software you may find here.

Compound of Two Tetrahedral Wedges

Posted on 16 September 2016 by RobertLovesPi

compound-of-two-wedges

I made this with Stella 4d, a program you can try for yourself right here.

A “Thumbs Up” for Google Classroom

Posted on 9 September 2016 by RobertLovesPi

This is my 22nd year of teaching, but my first year using Google Classroom. We’re finding it to be a useful tool. This, for example, is the diagram for the Atwood’s machine lab we are doing in Pre-AP Physical Science, beginning today. My students will find this waiting for them in their virtual classroom (on Chromebooks my school district provides), with discussion-prompts to get us started:

atwoods-machine-diagram

I had no idea that four years of blogging, here on WordPress, had been preparing me to use this teaching tool. However, active blogging does require one to develop some transferable skills, especially in fields (such as what I teach) which are similar to the topics of one’s blog, as is the case here.

Phantom Squares Obscuring M31

Posted on 4 September 2016 by RobertLovesPi

a long way to andromeda

I used a photograph by Aggelos Kechagias, as well as software (Stella 4d, available here) to create this .gif image. The black squares are those of a rotating great rhombicosidodecahedron.