A pleated surface on the boundary of the convex core.
A new claim could imply that a proof of one of the most important conjectures in number theory has been solved, which would be an astounding achievement. Mathematician Shinichi Mochizuki of Kyoto University in Japan has released a 500-page proof of the abc conjecture that proposes a relationship between whole numbers (related to the Diophantine equations).
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What is the source of that image of the pleated Teichmüller surface?
Here’s a link to the source:
http://www.msri.org/web/msri/scientific/programs/show/-/event/Pm121