Math Toys

Mathematica Eames Souvenir

Wikipedia has great info about Mathematica and where to see it. 

The Poincare Disk is a representation of non-Euclidean gemometry and tesselations can look amazing- M.C. Escher used this math for his famous Circle Limit woodcut.

Mathematica features a large Galton Board (click to get one).

Mathematica Eames Souvenir: from the 1961 opening of “Mathematica: A World of Numbers and Beyond” by the famous design team of Charles and Ray Eames this souvenir of card stock features a tessellation of the hyperbolic plane (a Poincaré Disk) with triangles on the front and on the obverse is the title of the exhibit but hidden within an anamorphic font. Amazing math art before the age of computer graphics! There are three versions of the exhibit and all can still be seen at museums in Boston, Atlanta, and Dearborn. 


The DeltaCELT Rattleback 

Get one here: 

From Etsy: BUY NOW: The DeltaCELT

The DeltaCELT: a new rattleback design where the indentations create an asymmetry in the distribution of mass that leads to rotation reversals when spun: 1) If spun clockwise, after about two full rotations, a complicated combination of friction, precession, and instability induced vibrations transforms the rotational energy into into end-to-end rattling (energy of oscillations) and then into rotational energy in the opposite direction. 2) If spun counter-clockwise, after about 30 full rotations the rotational energy translates into side-to-side oscillations leading to a clockwise reversal (swipe to see- less dramatic but still amazing). The design is made of solid brass and has the shape of a bisected prolate ellipsoid in the proportion of the mathematical constant δ =4.669.. (Feigenbaum dynamical constant) giving the name to this new design by astrophysicist Kenneth Brecher. The DeltaCELT comes with the polished slate spinning surface for optimal performance. 

Hyperbolic Holes

This inexpensive kit available here:

From Amazon: BUY NOW: Hyperbolic Holes Kit

Hyperbolic Holes: a straight rod, in this case a pencil, glides through a symmetrical pair of curved holes. The design is based on the hyperboloid, the 3D ruled surface traced by an offset rotating diagonal line. This device is sold as an inexpensive kit to assemble yourself, and includes a motor with geared drive and pre-cut pieces. The pencil is my addition- sharpened to just the right size to clear the curved openings.

Rolling Uphill Illusion

Get the 3D print file here:

From Thingverse: Download Now: Uphill Illusion

Learn more: The amazing illusions of Kokichi Sugihara

See the many other Sugihara Illusions: in my collection

Rolling Uphill Illusion: the ball bearings seemingly roll uphill as if attracted by magnets of some kind. What’s going on? Swipe for reveal as it is truly a matter of perspective. A wonderful take on an illusion invented by Kokichi Sugihara of Meiji University. 3D printed by my good friend @zathras5 (Roger Key) from a file designed by Julian Hardy.