Phys.org June 12, 2024
Using waves to explore our environment is a widely used paradigm, ranging from seismology to radar technology, and from biomedical imaging to precision measurements. The central aim is to gather as much information as possible about an object of interest by sending a probing wave at it and processing the information delivered back to a detector. An international team of researchers (Austria, France) demonstrated that an electromagnetic wave scattered at an object carries locally defined and conserved information about all of the object’s constitutive parameters. They introduced the density and flux of Fisher information for general types of wave fields and identified the corresponding sources and sinks of information through which all these new quantities satisfy a fundamental continuity equation. They experimentally verified their predictions by studying a movable object embedded in a disordered environment and measuring the corresponding Fisher information flux at microwave frequencies. According to the researchers their results improved the understanding of the generation and propagation of information and opened possibilities for tracking and designing the flow of information even in complex environments… read more. TECHNICAL ARTICLE
FI radiation patterns. Credit: Nature Physics, 10 June 2024