Tannakian Reconstruction: Recovering Hidden Structures from Functors

Tannakian Reconstruction

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Tannakian Reconstruction: Recovering Hidden Structures from Functors

I explain how Tannakian reconstruction allows us to recover the original structure of a category by superimposing images from all possible functors. Using an analogy of Bob photographing Alice's lights across a river, I show how combining these views reveals the hidden connections between objects. This process relies on fiber functors and the Yoneda embedding to prove that the totality of representations perfectly reconstructs the source morphisms.

"Like with any product, if any of its components is empty, the whole end is empty."

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