where each spin of the lathe reveals hidden beauty inside the wood. In this wood turning video I turn a piece of Beech which had a nasty crack in it, I could probably have turned it out but ...

"Normally a sphere can be turned inside out only if it has been torn. In differential topology one assumes that the surface can be pushed through itself, but then the problem is to avoid forming a ...

This video is about the problem of turning a sphere inside out, by passing the surface through itself, without making any holes or creases. Mathematicians believed the problem to be unsolvable ...