🛋️ Stat of the Day: Six decades ago, mathematician Leo Moser posed a question that has come to be known as the Moving Sofa Problem: When moving a 2-dimensional piece of furniture through an L-shaped hallway, what’s the largest shape that won’t get stuck?

Some obvious answers include a square with a side length exactly as long as the hallway (1 unit by 1 unit), or a semicircle with a radius of 1 unit (total area: ~1.57 units). However, those shapes are relatively small.

• In 1992, Joseph Gerver of Rutgers University proposed a uniquely shaped “sofa” (☝️) featuring an area of 2.2195 units.
• This was believed for decades to be the maximum possible amount, but researchers couldn’t prove it.

Until now…In a new 119-page paper, which is in the peer-review process, South Korean postdoctoral researcher Jineon Baek proved Gerver’s sofa is the largest possible shape that can successfully pass through the hallway.

🤔 Did You Know? Salt has been used as currency throughout human history. The word “salary” is even derived from the Latin word for salt (“sal”).

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