Polyhedral compounds | Polyhedral stellation

Compound of dodecahedron and icosahedron

In geometry, this polyhedron can be seen as either a polyhedral stellation or a compound. (Wikipedia).

Compound of dodecahedron and icosahedron
Video thumbnail

How to Construct a Dodecahedron

How the greeks constructed the Dodecahedron. Euclids Elements Book 13, Proposition 17. In geometry, a dodecahedron is any polyhedron with twelve flat faces. The most familiar dodecahedron is the regular dodecahedron with regular pentagons as faces, which is a Platonic solid. A regular dode

From playlist Platonic Solids

Video thumbnail

How to Construct an Icosahedron

How the greeks constructed the icosahedron. Source: Euclids Elements Book 13, Proposition 16. In geometry, a regular icosahedron is a convex polyhedron with 20 faces, 30 edges and 12 vertices. It is one of the five Platonic solids, and the one with the most faces. https://www.etsy.com/lis

From playlist Platonic Solids

Video thumbnail

Canonical structures inside the Platonic solids III | Universal Hyperbolic Geometry 51

The dodecahedron is surely one of the truly great mathematical objects---revered by the ancient Greeks, Kepler, and many mathematicians since. Its symmetries are particularly rich, and in this video we look at how to see the five-fold and six-fold symmetries of this object via internal str

From playlist Universal Hyperbolic Geometry

Video thumbnail

Regular polyhedra

This shows a 3d print of a mathematical sculpture I produced using shapeways.com. This model is available at http://shpws.me/q0PF.

From playlist 3D printing

Video thumbnail

The remarkable Platonic solids II: symmetry | Universal Hyperbolic Geometry 48 | NJ Wildberger

We look at the symmetries of the Platonic solids, starting here with rigid motions, which are essentially rotations about fixed axes. We use the normalization of angle whereby one full turn has the value one, and also connect the number of rigid motions with the number of directed edges.

From playlist Universal Hyperbolic Geometry

Video thumbnail

AlgTop8: Polyhedra and Euler's formula

We investigate the five Platonic solids: tetrahedron, cube, octohedron, icosahedron and dodecahedron. Euler's formula relates the number of vertices, edges and faces. We give a proof using a triangulation argument and the flow down a sphere. This is the eighth lecture in this beginner's

From playlist Algebraic Topology: a beginner's course - N J Wildberger

Video thumbnail

Ionic Solids, Molecular Solids, Metallic Solids, Network Covalent Solids, & Atomic Solids

This chemistry video tutorial provides a basic introduction into solids. It explains how to classify a solid as ionic solids, molecular solids or atomic solids. There are 3 different types of atomic solids that you need to be familiary with - metallic solids, Group 8A solids, and network

From playlist New AP & General Chemistry Video Playlist

Video thumbnail

What Are Allotropes of Metalloids and Metals | Properties of Matter | Chemistry | FuseSchool

What Are Allotropes of Metalloids and Metals Learn the basics about allotropes of metalloids and metals, as a part of the overall properties of matter topic. An allotrope is basically a different form of the same element, each with distinct physical and chemical properties. For example

From playlist CHEMISTRY

Video thumbnail

The Pop-up Dodecahedron

Instruction to download http://singingbanana.com/popupdodecahedron.pdf More information about the dodecahedron that I would have like to have gone into in this video http://uk.youtube.com/watch?v=-lqpSpje42o Dodecahedron at wikipedia http://en.wikipedia.org/wiki/Dodecahedron Plato

From playlist My Maths Videos

Video thumbnail

Math Mornings at Yale: Asher Auel - Wallpaper, Platonic Solids, and Symmetry

The Platonic solids-the tetrahedron, cube, octahedron, dodecahedron, and icosahedron-are some of the most beautiful and symmetric geometrical objects in 3-dimensional space. Their mysteries started to be unraveled by the ancient Greeks and still fascinate us today. In 1872, the German geom

From playlist Math Mornings at Yale

Video thumbnail

Group theory 27: The icosahedral group

This lecture is part of an online math course on group theory. The lecture is about a few examples of groups, in particular the icosahedral group. In it we see that the icosahedral group is the only simple group of order 60, and show that all larger alternating groups are simple.

From playlist Group theory

Video thumbnail

Further adventures in stereographic projection

These stereographic projection models are available from my Shapeways shop: https://www.shapeways.com/shops/henryseg?section=Stereographic+Projection The torch/flashlight is a Mini Maglite AAA LED flashlight (http://maglite.com/shop/mini-maglite-led-2-cell-aaa-flashlight.html).

From playlist 3D printing

Video thumbnail

AlgTop9: Applications of Euler's formula and graphs

We use Euler's formula to show that there are at most 5 Platonic, or regular, solids. We discuss other types of polyhedra, including deltahedra (made of equilateral triangles) and Schafli's generalizations to higher dimensions. In particular in 4 dimensions there is the 120-cell, the 600-c

From playlist Algebraic Topology: a beginner's course - N J Wildberger

Video thumbnail

Platonic and Archimedean solids

Platonic solids: http://shpws.me/qPNS Archimedean solids: http://shpws.me/qPNV

From playlist 3D printing

Video thumbnail

d60 deltoidal hexecontahedron

See http://thedicelab.com/ for more details. These dice are available at http://www.mathartfun.com/shopsite_sc/store/html/DiceLabDice.html

From playlist Dice

Video thumbnail

Rubenstein's cactus

Joint work with Rick Rubenstein. Available from Shapeways at http://shpws.me/r1iO

From playlist 3D printing

Video thumbnail

How to construct a Tetrahedron

How the greeks constructed the first platonic solid: the regular tetrahedron. Source: Euclids Elements Book 13, Proposition 13. In geometry, a tetrahedron also known as a triangular pyramid, is a polyhedron composed of four triangular faces, six straight edges, and four vertex corners. Th

From playlist Platonic Solids

Video thumbnail

Stanford Lecture: Don Knuth—"Hamiltonian Paths in Antiquity" (2016)

Computer Musings 2016 Donald Knuth's 23rd Annual Christmas Tree Lecture: "Hamiltonian Paths in Antiquity" Speaker: Donald Knuth About 1850, William Rowan Hamilton invented the Icosian Game, which involved finding a path that encounters all points of a network without retracing its steps.

From playlist Donald Knuth Lectures

Related pages

Icosahedral symmetry | Compound of two tetrahedra | Decagram (geometry) | Convex hull | Platonic solid | Vertex arrangement | Rhombic triacontahedron | List of Wenninger polyhedron models | Pentagon | Icosidodecahedron | Dodecahedron | Spherical polyhedron | Compound of cube and octahedron | Icosahedron | Symmetry group | Polyhedron | Stellation | Compound of small stellated dodecahedron and great dodecahedron | Deltoidal hexecontahedron | Petrie polygon | Geometry | Triangle | Dual polyhedron