According to AMBCrypto, a paper published by Peter Zimmerman from the Bank of England and the Federal Reserve Bank of Cleveland and Anantha Divakaruni from the University of Bergen shows that the Lightning Network has become increasingly centralized. They compared the Lightning Network data from April 1, 2018 and August 31, 2019, and found that the network structure has become more centralized, which is characterized by only a small number of highly connected users. During the above period, the number of participants in the Lightning Network increased fourfold from 1145 to 5699. However, the average number of nodes connected to each node t0 increased from only 7.7 to 11.4. This reduces the connectivity between nodes from 0.7% to 0.2%. The centrality of the eigenvectors of the five most closely connected nodes showed a peak, which indicates that the network "more and more depends on several core nodes."