I've been reading about Ed Witten at the Strings '95 conference. Oooh, that man's brainy. In fact, he's so smart I reckon he must be part beaver! [

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He gobsmacked the audience at Strings '95 by showing that, at low-energies, 10-dimensional superstring theory is equivalent to 11-dimensional supergravity. He equated momentum in the 11th dimension of supergravity as charge in the 10-dimensional superstring theory - and that got me thinking.

Could other properties of particles, such as spin and mass, also be the result of momentum in higher dimensions?