Chern-Simons action

The Chern-Simons action is a mathematical framework used in physics, particularly in the study of gauge theories and topological quantum field theories. It encodes how fields called connections interact in a space, capturing properties related to the space's shape and twists, independent of size or distance. This action depends on the geometry and topology of the underlying space, making it useful for understanding phenomena like quantum Hall effects and knot invariants. Essentially, it provides a way to describe certain physical systems where the focus is on their global, topological features rather than local details.