In an article by A. Borovik, “[Is mathematics special?][2]”, he talks about the fact that [carrying is a cocycle][1]. He then says

> [A student] discovered that carry is doing what cocycles frequently do: they are responsible for break of symmetry.

I have never thought about cocycles in this way. In what sense are cocycles often breaking symmetry? Are there any other examples of this?


  [1]: https://ncatlab.org/nlab/show/carrying
  [2]:http://www.lib.uni-bonn.de/PhiMSAMP/Book/