Its a transition between distinct operational phases of a dynamic system, iirc these can be described with a (my terminology may be a bit off here) topological

Its a transition between distinct operational phases of a dynamic system, iirc these can be described with a (my terminology may be a bit off here) topological phase diagram https://mitpress.mit.edu/books/dynamical-systems-neuroscience https://mitpress.mit.edu/books/dynamical-systems-neuroscienc...