Tag: Drawing

Geometry of the Motion of a Free Prolate Gyroscope (and the Power of Magnets)

How should I spin the story of the gyroscope this time? Imagine, you have a wonderfully crafted elongated ellipsoid from wood (shaped like a rugby ball). You built some apparatus that make it spin fast about its major axis. Probably you can make it spin with your bare hands – or you ask a tentacled…
Osculating Circles Revisited

Every squiggly line could be an image of the meandering trajectory of a particle. At each instant, the path has a direction and a curvature. Curvature can be represented by the circle that fits the curve best – the osculating circle. In a two-dimensional world, the osculating circles would lie flat in the same plane…
Diamond Cubic

Once upon a time I analyzed electron diffraction patterns. They looked like this: These patterns are the inverse of the crystal lattices, sort of. The regularity of the dots represents the symmetries of the physical crystal. To identify the material causing a certain pattern, you compared it with sample patterns in a “database”. I am…
Aharonov-Bohm Effect

It is often called the simplest example of topology impacting physics (Topology like “the shape of space”, like coffee mugs being donuts!). Charged particles move under the the influence of electric and magnetic fields. The concept of fields was once introduced to replace action at a distance: If one charge tugs on another, it does…
Mass Shell

Space and time are rotated into each other. Momentum and energy are as well. This rotation in four dimensions is of an unusual, hyperbolic kind. Which is the source of all so-called paradoxa in special relativity. Best to avoid thinking of clocks, rulers, trains, and observers. Just stick to the geometry. When a classical particle…
Postal Scales Now and Then

I’ve tried to stage it properly. But it just looks sad. Functional – and not inspiring: The white plastic casing already starts to yellow at the top, from years of bombardment with UV photons. Its function in our office had been replaced … by not sending invoices or contracts on paper anymore. Edit: The original…
Magneto Compass – Inverted Art

It has been quite a while since I have drawn my antique rotary phone as “negative art”. This phone features white letters on black background. At that time I had no idea that white gel pens exist, for drawing such letters. So, I “invented” inverted art – as usual, only to discover that many artists…
Dare to Be Negative!

Do you remember analog photo negatives? I still have some, tucked away deep in the archives. I always found them eerie and uncanny. Humans turned into zombies with black teeth. Burnt orange, weird cyan and violet everywhere. But what did I expect? We don’t have an intuition for addition or subtraction of colors. Would you…
On Descriptive Geometry

I keep forgetting I am writing for an international audience here! Having referred to Descriptive Geometry (DG) often, I doubt that everybody associates similar mental images with it. Anybody remembering the trace of a plane, for example? Learning about the history and culture of Descriptive Geometry, I realize it is rooted in a European tradition…
Coping with the AI Apocalypse

Painstakingly, I was putting the finishing touches on my analog geometric art – when this video popped into several of my social media feeds: We Need To Talk About AI… by Cool Worlds Podcast Cool Worlds Podcast is run by a team at Columbia University and usually features guests interviewed by physicist David Kipping. This…
Rolling Not Slipping – Story of a Twirling Ellipsoid

I can’t help it – I use the first title that pops into my mind! “Rolling, not slipping” is the punchline of a mathematical argument used in classical mechanics, in the theory of the motion of a gyroscope. But I am not going to do it justice in this blog post (apart from a math…
Unearthing a Time Capsule and Preserving a Fading Cathedral

My first creative endeavors (as an adult) were not drawings or paintings. It was the early web that made me pick colors by hand and stitch together HTML code snippets. The web of the early 2000s was a very different place from the modern social media era, built from many small independent sites and blogs,…
Spinning Projection – a Tiny Canvas Print, a Long Time in the Making

These spheres and lines have been haunting me. I have been writing about stereographic projection so often – and created so much related geometrical art – that I created a blog post just for curating all the links to my own articles: Stereographic Retrospective. This year, I have created a series of six drawings of…
$Hello to the Fediverse :)$

Hello to the Fediverse :)

Hello, people out there on Mastodon, Pixelfed, or whatever platform you use! You might have seen a weird collection of old posts reposted by my account today! Sorry :) This has been just me cleaning up minor stuff – not knowing that I have to turn off federation explicitly to avoid blasting out these old…
Poinsot’s Paper Spaceship (2025)

I’m presenting the recently completely series of artworks – and related physics blog posts – in its entirety! An ellipsoid is intersecting a sphere. Their intersection line is where the vector of angular momentum is seen to travel along – from the perspective of the spinning gyroscope. Four geometrical drawings, each based on the physics…
Geometry of the Physics of the Gyroscope – on a Coffee Mug!

Construct the Labyrinth from Which You Plan to Escape … has been the motto of the Oulipo movement, French writers and mathematicians who have boosted their creative writing by imposing arbitrary constraints. I had practiced Oulipo long before I knew the term. I just called it Search Term Poetry or Spam Poetry. I have been…
Evil Ellipsoids and Spheres (Poinsot’s Paper Spaceship #4)

Do you remember how photo negatives looked like? The inverted versions of the most common colors looked so unreal. Hues of orange, violet, or cyan that you never saw in the real world. Happy smiling human people looked like turquoise zombies with an evil grin. When creating this geometric drawing, I haven’t been thinking about…
Lissajous Trilogy on Canvas

Let me show you the genesis of my most involved watercolor pencils drawing so far! I have constructed 3D Lissajous figures on paper, projecting the three-dimensional world down to two dimensions. But I want my artworks to look three-dimensional, too! So, I am using a canvas stretched on wood. My experiments with canvas board taught…