Image: Torus from rectangle

Description: A torus can be constructed by two transformations on a rectangle. First, we bend along one direction, joining opposite sides, creating a cylinder. Then, we bend the cylinder so the ends are joined. The resulting figure is a torus. However, the second transformation does not preserve lengths on the surface, as can be observed by the extension and compression of the checkered pattern. Here's the diagram of this process:
Title: Torus from rectangle
Credit: Own work
Author: Lucas Vieira
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Usage Terms: Public domain
License: Public domain
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