By using the tiny imperfections in an optical fiber, they have invented a way to have a seismic monitor every 2m along a piece of dark fiber, all around cities

By using the tiny imperfections in an optical fiber, they have invented a way to have a seismic monitor every 2m along a piece of dark fiber, all around cities and along major highways.[0] [0] https://www.caltech.edu/about/news/caltech-and-city-pasadena-team-build-seismic-sensing-network https://www.caltech.edu/about/news/caltech-and-city-pasadena...