White spots appear on the teeth when the tooth’s enamel starts decomposing due to plaque. However, a wide range of cases can bring this erosion on and lead to decalcification. Here’s a quick overview ...

It’s a marvel to fit a frame and mattress for a bulky piece of furniture inside another, equally bulky piece of furniture; also, you’ve probably slept or sat on a sleeper sofa that fell short ...

A mathematician at Yonsei University, in Korea, claims to have solved the moving sofa problem. Jineon Baek has posted a 100+-page proof of the problem on the arXiv preprint server. Most people who ...

Kelsey Mulvey is a lifestyle editor and writer. She has written for publications like Wall Street Journal, Business Insider, Wallpaper.com, New York Magazine, and more. Sarah Lyon is a freelance ...