3Blue1Brown: Exponential growth and epidemics. (YouTube, 8:56min)
“A good time for a primer on exponential and logistic growth, no? […] While this video uses COVID-19 (aka the Coronavirus) as a motivating example, the main goal is simply a math lesson on exponentials and logistic curves.”
NPR: Math Looks The Same In The Brains Of Boys And Girls, Study Finds.
“There’s new evidence that girls start out with the same math abilities as boys.
A study of 104 children from ages 3 to 10 found similar patterns of brain activity in boys and girls as they engaged in basic math tasks, researchers reported Friday in the journal Science of Learning.
“They are indistinguishable,” says Jessica Cantlon, an author of the study and professor of developmental neuroscience at Carnegie Mellon University.
The finding challenges the idea that more boys than girls end up in STEM fields (science, technology, engineering, and mathematics) because they are inherently better at the sort of thinking those fields require. It also backs other studies that found similar math abilities in males and females early in life.”
NPR: New Study Challenges The Assumption That Math Is Harder For Girls. “Research shows that when boys and girls as old as 10 do math, their patterns of brain activity are indistinguishable. The finding is the latest challenge to the idea that math is harder for girls.”
“Geary says differences seem to show up later and involve very high-level math tasks. His own research has found that in most countries, female students perform just as well as male students in science-related subjects. Yet paradoxically, Geary says, females are less likely to get degrees in fields like math and computer science if they live in wealthier countries with greater gender equality.”
3Blue1Brown: The most unexpected answer to a counting puzzle and So why do colliding blocks compute pi? and How colliding blocks act like a beam of light…to compute pi. (YouTube, 5:12min and 15:15min and 14:40min)
The connection between the initial experiment and the calculation of π is surprising, and finding two different solutions in physics is even more astounding. The videos are extremely well done, and the presentation helps a lot with understanding the mathematical manipulations.
Link via Futility Closet.
Futility Closet: Even Sevens.
I know a lot of rules to determine divisibility, but I never knew there were any for divisibility by seven. Here’s one!
Vihart: Peace for Triple Piano. (YouTube 3D video, 4:15min)
This has got to be one of the most amazing things done with a 3D camera I’ve ever seen. Pro tip: Watch this in fullscreen mode on your phone so you can look around by moving the entire phone, and use headphones to get the full 3D sound effect as well.
Make sure to also watch
Henry Segerman: The Making of “Peace for Triple Piano”. (YouTube video, 13:52min including a “flat” version of the above 3D video).
In this video Vi Hart and Henry Sergerman explain how the video works: how they made one grand piano and one Vi look like three, but one Henry look like only two at the same time.
Vi writes a little more about this project on her weblog: Vihart.com: Peace for Triple Piano.
(This was published back in February, but I only now realized that the RSS feed of this YouTube channel stopped working.)