For those who have wrestled a bulky couch around a tight corner and lamented, “Will this even fit?” mathematicians have heard your pleas. Geometry’s “moving sofa problem a ...

BAEK: The moving-sofa problem asks us to find the largest two-dimensional shape, a 2D sofa, that you can fit around a 90-degree corner without getting stuck and making its way all through.

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 ...

For decades, mathematicians tried to come up with the optimal sofa shape to move around a corner. Post-doctoral student Jineon Baek posted a 100-page proof that claims to solve the problem.