This post is finally going to get back to some ML related topics.
In fact, the original reason I took that whole math-y detour in the previous
posts was to more deeply understand this topic. It turns out trying to
under tensor calculus and differential geometry (even to a basic level) takes a
while! Who knew? In any case, we're getting back to our regularly scheduled program.

In this post, I'm going to explain one of the applications of an abstract
area of mathematics called hyperbolic geometry. The reason why this area is of
interest is because there has been a surge of research showing its
application in various fields, chief among them is a paper by Facebook
researchers [1] in which they discuss how to utilize a model of hyperbolic
geometry to represent hierarchical relationships. I'll cover some of
the math weighting more towards intuition, show some of their results, and also
show some sample code from Gensim. Don't worry, this time I'll try much harder
not going to go down the rabbit hole of trying to explain all the math (no
promises though).

(Note: If you're unfamiliar with tensors or manifolds, I suggest getting a quick
overview with my previous two posts:
Tensors, Tensors, Tensors and
Manifolds: A Gentle Introduction)

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