The Sydler π/4 polyhedron. The shape that should be impossible.
15
votes
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When you make a mathematical knot using elastic material you get jumping loops, and challenging puzzles
8 votes -
If you try to pass a bouncy ball under a table, if it hits the underside of the table it will just bounce back out the way it came
8 votes -
A brief history of tricky mathematical tiling
10 votes -
The mathematician who sculpted the shape of space - obituary for Eugenio Calabi
13 votes -
Polyhedra world
8 votes -
The golf ball paradox
11 votes -
Steffen's polyhedron is a flexible concave polyhedron. Euler thought such a shape was impossible. I also show infinitesimally flexible polyhedrons and bistable polyhedrons.
13 votes -
The spool paradox
4 votes -
UK hobbyist discovers new unique shapes, stunning mathematicians
17 votes -
The derivative isn't what you think it is
8 votes -
Why the brain’s connections to the body are crisscrossed
6 votes -
Can water solve a maze?
11 votes -
An aperiodic monotile exists!
21 votes -
The turntable paradox: A ball on a spinning turntable won't fly off as you might expect. In fact the ball will have it's own little orbit exactly 2/7th the angular speed of the table. Here's why.
6 votes -
Penrose Unilluminable Room is a room with mirrored walls that can't be fully illuminated by a single point source of light
3 votes -
The hyperbolic geometry of DMT experiences
7 votes -
Alice, Bob, and the average shadow of a cube
4 votes -
Getting an odd number of cogs in a loop to turn
7 votes -
The illusion only some can see
12 votes -
The universal geometry of geology
10 votes -
There are forty-eight regular polyhedra
8 votes -
A surprising Pi and 5
3 votes -
A parallelogram puzzle
3 votes -
17 Klein Bottles become 1 - ft. Cliff Stoll and the glasswork of Lucas Clarke
12 votes -
A molecular near miss
7 votes -
A quick and dirty introduction to Exterior Calculus (Stoke's Theorem)
6 votes -
Heesch numbers and tiling
7 votes -
Toroflux paradox: making things (dis)appear with math
5 votes -
Twenty questions (of maddening, delicious geometry)
9 votes -
How to convert a non-math-lover (Dandelin spheres)
3 votes -
Balls and cones
4 votes