Category Archives: Math Munch

Harriss Spiral, Math Snacks, and SET

Happy New Year, and welcome to this week’s Math Munch!

The Harriss Spiral

Exciting news, folks! The Golden Ratio curve– that beautiful spiral that everyone adores– has evolved. And not into a freak of nature, either! Into something– dare I say it?– even more beautiful…

Meet the Harriss spiral. It was discovered/invented by mathematician and artist Edmund Harriss (featured before here and here) when he began playing around with golden rectangles. A golden rectangle is a very special rectangle, whose sides are in a particular proportion. You can read more about them here— but what’s most important to this new discovery is what you can do with them. If you make a square inside a golden rectangle you get another golden rectangle– and continuing to make squares and new golden rectangles inside of ever-shrinking golden rectangles, and drawing arcs through the squares, is one way to make the beautiful golden ratio spiral.

Edmund Harriss decided to get creative. What would happen, he wondered, if he cut the golden rectangle into two similar rectangles (same shape, just one is a scaled-down version of the other) and a square? And then what if he did the same thing to the new rectangles, again and again to make a fractal? Edmund’s new golden rectangle fractal makes this pattern, and when you draw a spiral through it, you get a lovely branching shape.

But don’t take my word for it. Math journalist Alex Bellos broke the news just this week in his article in The Guardian. His article explains much, much more than I can here– check it out to learn many more wonderful things about the Harriss spiral (and other spirals that Harriss has created…)!

(Bonus: Here’s a GeoGebra demonstration created by John Golden that builds the Harriss Spiral. It’s awesome!)

Next up is a site that sounds quite a lot like Math Munch. But it’s all games and cartoons, all the time. (Maybe that means you’ll like it better…) Check out Math Snacks, a site developed by a group of math educators at New Mexico State University. They worked hard to create games and animations that are both fun and full of interesting math.

One of my favorite games on Math Snacks is called Game Over Gopher.In this game, you have to save your carrot from an army of gophers by placing little machines that feed the gophers. Where’s the math, you may wonder? Placing the gopher-feeders and the other equipment that can help you save the carrot requires you to think carefully about geometry and coordinates.

Finally, speaking of games, here’s one of my favorites. I love to play SET, and I recently found a way to play online– either against a friend or against the computer. Click on this link to start your own game!

To play SET, you deal 12 cards. Then, you try to find a group of 3 cards that all share and all don’t share the same characteristics. For example, in the picture to the right– do you see the cards with the empty red ovals? They’re all the same shape, shading, and color (oval, empty, red), but they’re all different numbers (1, 2, and 3). Can you find any other sets in the picture? (Hint: One involves purple.)

Want to hone your SET skills without competing? Here’s a daily SET puzzle to challenge you.

Enjoy the games (and maybe invent a spiral of your own) and bon appetit!

Nice Neighbors, Spinning GIFs, and Breakfast

A minimenger.

A minimenger.

Welcome to this week’s Math Munch!

Math projects are exciting—especially when a whole bunch of people work together. One example of big-time collaboration is the GIMPS project, where anyone can use their computer to help find the next large prime number. Another is the recent MegaMenger project, where people from all over the world helped to build a giant 3D fractal.

But what if I told you that you can join up with others on the internet to discover some brand-new math by playing a webgame?

Chris Staecker is a math professor at Fairfield University. This past summer he led a small group of students in a research project. Research Experiences for Undergraduates—or REUs, as they’re called—are summer opportunities for college students to be mentored by professors. Together they work to figure out some brand-new math.

The crew from last summer's REU at Fairfield. Chris is furthest in the back.

The crew from last summer’s REU at Fairfield. Chris is furthest in the back.

The irreducible digital images containing 1, 5, 6, and 7 points.

The irreducible digital images containing 1, 5, 6, and 7 “chunks”.

Chris and his students Jason Haarmann, Meg Murphy, and Casey Peters worked on a topic in graph theory called “digital images”. Computer images are made of discrete chunks, but we often want to make them smaller—like with pixel art. So how can we make sure that we can make them smaller without losing too much information? That’s an important problem.

Now, the pixels on a computer screen are in a nice grid, but we could also wonder about the same question on an arbitrary connected network—and that’s what Chris, Jason, Meg, and Casey did. Some networks can be made smaller through one-step “neighbor” moves while still preserving the correct connection properties. Others can’t. By the end of the summer, the team had come up with enough results about digital images with up to eight chunks to write about them in a paper.

To help push their research further, Chris has made a webgame that takes larger networks and offers them as puzzles to solve. Here’s how I solved one of them:

NiceNeighbors

See how the graph “retracts” onto itself, just by moving some of the nodes on top of their neighbors? That’s the goal. And there are lots of puzzles to work on. For many of them, if you solve them, you’ll be the first person ever to do so! Mathematical breakthrough! Your result will be saved, the number at the bottom of the screen will go up by one, and Chris and his students will be one step closer to classifying unshrinkable digital images.

Starting with the tutorial for Nice Neighbors is a good idea. Then you can try out the unsolved experimental puzzles. If you find success, please let us know about in the comments!

Do you have a question for Chris and his students? Then send it to us and we’ll try to include it in our upcoming Q&A with them.

 

Next up: you probably know by now that at Math Munch, we just can’t get enough of great mathy gifs. Well, Sumit Sijher has us covered this week, with his Tumblr called archery.

Here are four of Sumit’s gifs. There are plenty more where these came from. This is a nice foursome, though, because they all spin. Click to see the images full-sized!

tumblr_mdv99p6WcP1qfjvexo1_500

How many different kinds of cubes can you spot?

This one reminds me of the Whitney Music Box.

This one reminds me of the
Whitney Music Box.

Whoa.

Clockwise or counterclockwise?

Clockwise or counterclockwise?

I really appreciate how Sumit also shares the computer code that he uses to make each image. It gives a whole new meaning to “show your work”!

Through Sumit’s work I discovered that WolframAlpha—an online calculator that is way more than a calculator—has a Tumblr, too. By browsing it you can find some groovy curves and crazy estimations. Sumit won an honorable mention in Wolfram’s One-Liner Competition back in 2012. You can see his entry in this video.

And now for the most important meal of the day: breakfast. Mathematicians eat breakfast, just like everyone else. What do mathematicians eat for breakfast? Just about any kind of breakfast you might name. For some audio-visual evidence, here’s a collection of sound checks by Numberphile.

Sconic sections. Yum!

Sconic sections. Yum!

If that has you hungry for a mathematical breakfast, you might enjoy munching on some sconic sectionsa linked-to-itself bagel, or some spirograph pancakes.

Bon appetit!

Mars, Triangulation, and LOMINOES.

Welcome to this week’s Math Munch!

First things first, I simply must mention a video that one of our readers sent us. Lily Ross was inspired by a recent post and created this amazing fake movie trailer!!! WOW! Thank you, Lily!

The video has been added to our Readers’ Gallery. Send us your creations and we’ll add them too.


Did you know that NASA is planning to send people to Mars around the year 2030? How far away would they be going? Click the picture to find out. It’s incredibly cool.

How Far is Mars?

How far is it to Mars?

Mars

Mars

The Moon

The Moon

distancetomars.com is an interactive website that answers the question, “how far is it to Mars?” It was created by a pair of designers, David Paliwoda and Jesse Williams. Think of how long that took to get there, and now realize that it takes light 3 times longer (since we were traveling impossibly fast, at 3 times the speed of light). That’s 3 light-minutes, so when we look at “the red planet,” we are seeing light that took more than 3 minutes to make the trip from Mars to our eye. We’re seeing what Mars looked like 3 minutes in the past!!! That’s pretty cool, I’d say.


Triangulation #9

Triangulation #9

Up next, another interactive website experience. This one is a series of interactive digital art — a sort of meditation on the essence of the triangle. Check out Triangulation.  Can you imagine adding a page to this? What would you design? Maybe you could use Scratch to actually make it!

Thanks to our friend, Malke Rosenfeld, for sending us this.

Screen Shot 2014-12-05 at 10.21.18 PM Screen Shot 2014-12-05 at 10.23.09 PM Screen Shot 2014-12-05 at 10.24.40 PM

Before we get to our last item this week, a couple of important announcements. As in prior years, Plus Magazine is hosting a mathematical advent calendar. Each day, a new number becomes clickable, linking to a page about nifty math stuff.

The 2014 Plus Magazine Mathematical Advent Calendar

The 2014 Plus Magazine Mathematical Advent Calendar

I also want to mention that The Aperiodical (an awesome (fairly advanced) math blog) is hosting a Math Pun Conmpetition!!! Here’s my submission, for those with a little bit of plane geometric knowledge:

Q: Why was it so hard for the equilateral quadrilateral to get home after school?

A: It got on the rhom BUS!

Rggie Rhombus


OK, now on to our last item of the week. Here it is…

A Pot-Pourri of People, Pictures, Places, Penrose Patterns, Polyhedra, Polyominoes, Posters, Posies, and Puzzles! (How about that?)

Alan Schoen with a model of a gyroid

Alan Schoen with a model of a gyroid

I don’t know a whole lot about Alan Schoen, but his website has some pretty enticing images on it. Really, all I know about Schoen is that he discovered the Gyroid when he worked at NASA in 1970. He also created The Geometry Garret, a website full of cool stuff.

The thing that I want to share is something I’ve never seen before – LOMINOES. These are polyominoes, like the ones we’ve featured at least twice before, but they are simply in the shape of an L. Alan wrote a 10-page booklet on the subject as well as a much longer book. (147 pages!)

They’re both worth poking through. If an image grabs your fancy, start reading and see what you can learn.

Screen Shot 2014-12-06 at 1.52.16 PMHave a great week and bon appetit!