Cocycles

Why is it interesting?

"In field theory and in modern elementary particle theory, cocycles are used to describe anomalies." (Source)

1-cocycles are used to understand anomalies in the Lagrangian framework. The 1-cocycles show up in the non-conservation of classically conserved currents.

2-cocycles are used to understand anomalies in the Hamiltonian framework. They have the effect that it becomes impossible to satisfy Gauss' law. (Source)

Layman

Explanations in this section should contain no formulas, but instead colloquial things like you would hear them during a coffee break or at a cocktail party.

Student

For a great introduction see https://inspirehep.net/record/213998/files/v15-n3-p99.pdf and chapter III in Analysis On Infinite Dimensional Manifolds: Schrodinger Representation For Quantized Fields by R. Jackiw

Researcher

The motto in this section is: the higher the level of abstraction, the better.
Common Question 1
Common Question 2

Examples

Example1
Example2:

History