IEEE/CAA Journal of Automatica Sinica
Citation:  D. Wang, W. Chen, and L. Qiu, “The first five years of a phase theory for complex systems and networks,” IEEE/CAA J. Autom. Sinica, vol. 11, no. 8, pp. 1728–1743, Aug. 2024. doi: 10.1109/JAS.2024.124542 
In this paper, we review the development of a phase theory for systems and networks in its first five years, represented by a trilogy: Matrix phases and their properties; The MIMO LTI system phase response, its physical interpretations, the small phase theorem, and the sectored real lemma; The synchronization of a multiagent network using phase alignment. Towards the end, we also summarize a list of ongoing research on the phase theory and speculate what will happen in the next five years.
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