Recently, the Soft Matter and Active Matter Collaborative Research Group of Shanghai Jiao Tong University (Matteo Baggioli Group of Wilczek Quantum Center and Jie Zhang Group of Institute of Natural Sciences / School of Physics and Astronomy) made important progress in the study of local vibration of active particulate matter. Based on the experiment of active Brownian particle system, the research group confirmed the local vibration of strings, and its corresponding zero group velocity dispersion relation predicted two years ago. This study is of great significance for understanding the singularity of the intrinsic vibration of amorphous solids, which is a mystery left to be solved in the last century.
