Digital Chalk - Nathan Doing Topology PhD Qualifying Exam Problems (Live)

 ... on some sort of pen-tablet. It's almost legible on my phone. No pretty colors though, ...

They don't like circular reasoning at UTexas! 


The next problem:


He does explain that a path is some function from the unit interval [0,1] to points in X, so I guess it takes 0 to x and 1 to y and for points in between it traces out the (presumably continuous) path in X, ...


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Here's the video about Lawvere's fixpoint theorem:

See also N.S. Yanofsky, A Universal Approach to Self-Referential Paradoxes.

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