The original link looks like a scratchpad/notes page to me. For insight into John Baez's ideas around this time, try the slides from this colloquium: http://ma

The original link looks like a scratchpad/notes page to me. For insight into John Baez's ideas around this time, try the slides from this colloquium: http://math.ucr.edu/home/baez/quantum_spacetime/ http://math.ucr.edu/home/baez/quantum_spacetime/ (http://math.ucr.edu/home/baez/quantum_spacetime/qs.pdf http://math.ucr.edu/home/baez/quantum_spacetime/qs.pdf) Urs Schreiber currently is at the forefront of where this line of mathematics ties in with fundamental physics. Here is a series he has started recently: https://www.physicsforums.com/insights/20-years-ago-today-m-theory-conjecture/ https://www.physicsforums.com/insights/20-years-ago-today-m-... Baez's higher dimensional algebra program formed a large part of the heritage to these ideas.