The Dehn Invariant - Numberphile

It was #3 on Hilbert’s list of the most important problems in mathematics - until his student solved it. More links & stuff in full description below ↓↓↓ Featuring Daniel Litt, currently at the Institute for Advanced Study - David Hilbert’s problems: ’s_problems Max Dehn’s famed proof: Numberphile is supported by the Mathematical Sciences Research Institute (MSRI): http://b