Google has changed the commenting system on YouTube so that you need to be a Google Plus user to post; the new system uses algorithms to promote some comments above others, and has the perverse effect of making trolls more visible. Vi Hart, the incomparable math-vlogger (and a regular favorite around here) describes how Google's decision to double down on its flagging Facebook-alike G+ service by ramming YouTube users into it has made her lose faith in the service: now her regular, good commenters comments hover at the bottom of the pile, while hateful trolls whose messages generate a lot of replies are judged "good" by G+ and promoted to the top.

The promise of G+ in the beginning was that making people use their real names would incentivize them to behave themselves. It's abundantly clear now that there are more than enough people who are willing to be jerks under their real names. In the meantime, people who have good reason not to post under their own names -- vulnerable people, whistleblowers, others -- are now fully on display to those sociopaths who are only too happy to press the attack with or without anonymity. Read the rest

We've featured doodling, fast-talking YouTube mathematician Vi Hart a lot here, but her latest, a 30-minute extended mix, is absolutely remarkable, even by her high standards. For 30 glorious minutes, Ms Hart explores the nature of randomness and pattern, using Stravinsky's 12-tone music as a starting-point and rocketing through constellations, the nature of reality, Borges's library, and more. On the way, she ends up with a good working definition of creativity, and explores the dilemma of structure versus creation. Brava, Ms Hart, you have outdone yourself! Plus, I like your copyright jokes.

Twelve Tones Read the rest

This fantastic video by Vi Hart shows you what the math of music looks like in a visual representation — or, should that be "what visual frieze patterns sound like when turned into music"?

Frieze patterns are symmetrical repeating patterns that show up in architecture, art, and even our model of DNA. According to Hart, this video is:

A visual and musical expression of mathematical symmetry groups. The transformations done to the video are equivalent to the transformations done to the notes.

Very cool to watch! Here's the video link.

Thanks, Peter Newbury!

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Vi Hart is Khan Academy's professional mathemusician. (Yeah, I KNOW, right?) And, this year, she's making the most delightfully nerdy Thanksgiving dinner ever.

It begins with green bean matherole, topped with fried Borromean onion rings. But, besides the fact that it's finished with crispy, delicious hyperbolic geometry, what makes the matherole a matherole?

Vectors. Like the rings, vectors are part of geometry. They've got a magnitude (think: size of the green bean) and they've got a direction (think: which way the green bean is pointing). Most importantly, a single vector can be part of a field of vectors. And that, my friends, is an excellent starting point for a 9 x 13 pan full of beans. Read the rest

[Video Link] By Vi Hart, about today's big physics news. (thanks, Kathleen McGivney!). Read the rest

[Video Link] To alleviate the boredom of math class, Vi Hart has taken to experimenting with squiggling. Be sure to check out Vi's other delightful math geek videos. (Via Cynical-C)

Many more posts about Vi Hart on Boing Boing here. Read the rest

"Linkage" is a technical/mechanical name for a relatively simple concept that's played a big role in daily life since the Industrial Revolution.

Imagine four rigid bars of different lengths, connected into a chain by three mobile joints. Add one more joint to the end, close the loop, and you have a linkage. You can use that linkage to change one type of motion—say, a spinning motor—into a completely different, usually very specific, type of motion. For instance, the windshield wipers on your car swish back and forth in time, the way they do, because their movement is controlled by a four-bar linkage similar to the one I just described.

Recreational mathematician Vi Hart has another way of explaining linkages, involving a good, fresh snowfall and the human body. Enjoy!

Thanks for Submitterating, akputney! Read the rest