On April 23, the reporter learned from the official website of the Chinese Academy of Sciences that the team of Guo Guangcan, an academician of the CAS Member and professor of the University of Science and Technology of China, has made new progress in the research of quantum network nonlocality. The team, Li Chuanfeng, Huang Yunfeng, Zhang Chao and others, cooperated with theoretical physicists from Spain, Switzerland and other countries to experimentally verify the non locality of the whole network in the star shaped quantum network for the first time. It is reported that this achievement was recently published in the international journal Nature Communications. Bell nonlocality has always been a research hotspot in the field of quantum information. In recent years, people have begun to explore non locality in more complex quantum networks containing multiple independent sources. Due to the inclusion of multiple independent latent variables, quantum networks can generate completely new quantum correlations that differ from traditional Bell nonlocality. Among them, the Bilocal model is the simplest and most studied quantum network at present, that is, two independent entanglement sources allocate entanglement pairs to three observer, similar to the scene of entanglement swapping, and the intermediate node receives two particles and makes Belky measurements to make the whole network generate nonlocal correlation. However, the previously defined non locality of the network cannot characterize the non classicality of all sources in the entire network, and in most cases it can degenerate into a violation of the standard Bell inequality, and intermediate nodes do not need to use entanglement measurement. Therefore, physicists have proposed the concept of global non locality, which requires all sources in the network to distribute non classical resources that can be used to authenticate the non classical properties of fully connected networks. At present, the non locality of the entire network has only been tested in the simplest biocal model. It is reported that in this work, the research team achieved breakthroughs in theory and experiment, successfully verifying the global non locality in more complex star networks. It is understood that this is the first verification of the non locality of the entire network in complex networks, and it is of great significance for the application of large-scale quantum networks, especially in ensuring the security of quantum communication protocols. (New News Agency)