Seb writes, "Citizen Maths is a new CC-BY licensed open online maths course produced in the UK for adults and college students who want to improve their grasp of maths at what in the UK is known as Level 2 (the level that 16 year old school leavers are expected to reach, though many do not)."

# Citizen Maths: open, free math education for adults

# Mathematician Edward Frenkel on whether the universe is a simulation

Regular BB readers know one of my favorite head trips is the idea that we're living in a simulation or control system of some kind. Decades before The Matrix, folks like Jacques Vallee, John Keel, Stephen Wolfram, Rudy Rucker, Hans Moravec, and Ed Fredkin explored this notion. And of course it's also been the subject of countless science fiction novels. In recent years, Oxford philosopher Nick Bostrom developed a mathematical argument to support the mind-bending theory. A week ago, UC Berkeley mathematician Edward Frankel, author of Love and Math: The Heart of Hidden Reality, summed up the Simulation Argument in the New York Times Sunday Review and asked whether we can test the hypothesis.

Is the Universe a Simulation? *(Thanks, Marina Gorbis!)*

# The Simpsons and Their Mathematical Secrets

*The Simpsons *is arguably the most successful television show in history. Inevitably, its global appeal and enduring popularity have prompted academics (who tend to overanalyze everything) to identify the subtext of the series and to ask some profound questions.

**Read the rest**

# Video: How to make chocolate out of nothing

In this video, Mariano Tomatis shows how to create chocolate out of nothing. Here is his explanation of this wonderful phenomenon, known as a missing square or vanishing area puzzle. *(Thanks, Ferdinando Buscema!)*

# Pi as music

[π] is a lovely and simple page that "explores the musical rhythm within 100,000 digits of π, an irrational number. #1 = Day | #0 = Night | #2–9 = La Musica." [π] *(3.14-pi.net)*

# Engraving a Klein bottle with an Eggbot

The Evil Mad Scientists were presented with a challenge: inscribe one of Cliff Stoll's hand-blown Klein bottles, an object of surpassing beauty and odd topology. They modified an Eggbot plotter to etch the surface of a Klein bottle with a diamond engraver attachment.

# Cartoon Introduction to Statistics: perfect way to get excited about stats

The Cartoon Introduction to Statistics is a new book by Grady Klein and Alan Dabney that is a top-notch introductory grounding in statistical concepts told through a series of witty, funny cartoons that relate stats to everything from fish populations to alien opinion surveys. This is a *very* introductory text, and it assumes that you know nothing about stats -- not even why you'd want to know more about the subject. The book tackles both the task of providing a grounding in statistical concepts (mean/median, standard deviation, null hypothesis, random sampling, confidence intervals, etc) and explaining in clear and exciting ways why you'd care about any of this stuff.

The authors do a great job of conveying the source material in clear, stepwise fashion, and made the wise decision to put the equations at the back of the book in an appendix called "The Math Cave." They don't delve deeply into any intermediate subjects like assessing correlation (for this, I highly recommend 1993's The Cartoon Guide to Statistics by Larry Gonick and Woollcott Smith, about which I can't say enough great and enthusiastic things), but that's probably a wise tactical decision. Confining the material to basics makes the whole work into an unqualified success.

# Goldberg polyhedra field guide [Video]

This guy sure knows how to have fun with Goldberg polyhedra!

# Is math real?

Here's a great video pondering the objective reality of mathematics, and running down all the different schools of thought on where mathematical truth comes from -- does it exist outside of systems of codification by intelligent beings, as an eternal part of the universe; or is it something that we invent through codification?

Is Math a Feature of the Universe or a Feature of Human Creation? | Idea Channel | PBS
(*Thanks, Dad!*)

# Beast Academy: grade three math textbooks in monster comics form

Beast Academy is a set of grade three math textbooks and practice books structured as comic books about monsters. The books are "aligned to the common core state standards for grade three," if that matters to you. What's more significant is that they're actually really good math textbooks that introduce their subjects in a clear and easy-to-follow fashion, carefully linking each concept to the last; and the exercises are lively, fun, and built around stories that dovetail smoothly into puzzles, games, and other ways of putting the knowledge into practice. The monsters are great, too -- wonderful illustrations from Erich Owen, whose work you may recognize from the graphic novel adaptation of my story I, Robot.

# Triple-nested Klein bottle

Here's glassblower Alan Bennett's astounding triple-nested Klein bottle, a beautiful thing:

A single surface model made by Alan Bennett in Bedford, United Kingdom. It consists of three Klein bottles set inside each other to produce, when cut, three pairs of single-twist Mobius strips. A Klein bottle has no edges, no outside or inside and cannot be properly constructed in three dimensions.

Klein bottle, 1995.
(*via Neatorama*)

(*Image: Science Museum/Science & Society Picture Library*)

# Another prime number down, infinity to go

# HOWTO re-create the Scrooge McDuck "Gold Coin Swim"

*the Billfold*today, a wonderful and mathematically precise post that explains exactly “how much money do I need to create giant floes of gold in a private vault and dive into it like Scrooge McDuck?”

*(thanks, Dean Putney!)*