Generic balanced synchrony patterns in network dynamics

Abstract: Coupled cell networks are specific ordinary differential equations with symmetry constraints, which are described by a given directed graph, with cells and arrows divided into several types. The generated dynamics can model, for example, those of neural networks. This type of systems and their emerging symmetries has been the subject of intense study, particularly by Golubitsky, Stewart and their co-authors. In the present article, we show that, for a generic vector field $f$, the synchrony patterns of the solutions of $\dot x(t)=f(x(t))$ are always balanced. This roughly means that the symmetries observed in a solution, such as synchronisation in two different cells, must come from the symmetries imposed by the geometry of network. By doing so, we are completing the proof of several conjectures stated in previous works, including the rigid synchrony conjecture, the full oscillation conjecture and the observation of constant states