Molnar Ferenc, Nishikawa Takashi, Motter Adilson E
Department of Physics and Astronomy, Northwestern University, Evanston, IL, USA.
SimpleRose Inc, 1017 Olive Street, Suite 800, Saint Louis, MO, 63101, USA.
Nat Commun. 2021 Mar 5;12(1):1457. doi: 10.1038/s41467-021-21290-5.
Behavioral homogeneity is often critical for the functioning of network systems of interacting entities. In power grids, whose stable operation requires generator frequencies to be synchronized-and thus homogeneous-across the network, previous work suggests that the stability of synchronous states can be improved by making the generators homogeneous. Here, we show that a substantial additional improvement is possible by instead making the generators suitably heterogeneous. We develop a general method for attributing this counterintuitive effect to converse symmetry breaking, a recently established phenomenon in which the system must be asymmetric to maintain a stable symmetric state. These findings constitute the first demonstration of converse symmetry breaking in real-world systems, and our method promises to enable identification of this phenomenon in other networks whose functions rely on behavioral homogeneity.
行为同质性对于相互作用实体的网络系统运行通常至关重要。在电网中，其稳定运行要求发电机频率在整个网络中同步——从而保持同质性，先前的研究表明，通过使发电机同质化可以提高同步状态的稳定性。在此，我们表明，通过使发电机适当地异质化，还可以实现显著的额外改进。我们开发了一种通用方法，将这种违反直觉的效应归因于逆对称性破缺，这是一种最近发现的现象，即系统必须不对称才能维持稳定的对称状态。这些发现首次证明了现实世界系统中存在逆对称性破缺，我们的方法有望在其他功能依赖于行为同质性的网络中识别出这一现象。
