Energy.

A link of information entropy and kinetic energy for quantum many-body systems. Abstract A direct connection of information entropy S and kinetic energy T is obtained for nuclei and atomic clusters, which establishes T as a measure of the information in a distribution. It is conjectured that this is a universal property for fermionic many-body systems. We also check rigorous inequalities previously found to hold between S and T for atoms and verify that they hold for nuclei and atomic clusters as well. These inequalities give a relationship of Shannon's information entropy in position-space with an experimental quantity i.e. the rms radius of nuclei and clusters.