We characterize the collective phenomena of a liquid market. By interpreting
the behavior of a no-arbitrage N asset market in terms of a particle system
scenario, (thermo)dynamical-like properties can be extracted from the asset
kinetics. In this scheme the mechanisms of the particle interaction can be
widely investigated. We test the verisimilitude of our construction on
two-decade stock market daily data (DAX30) and show the result obtained for the
interaction potential among asset pairs.Comment: 4 pages, svjour.cls, 3 figures, to appear in The European Physical
Journal