Spectral-statistics properties of the experimental and theoretical light   meson spectra
  We present a robust analysis of the spectral fluctuations exhibited by the light meson spectrum. This analysis provides information about the degree of chaos in light mesons and may be useful to get some insight on the underlying interactions. Our analysis unveils that the statistical properties of the light meson spectrum are close, but not exactly equal, to those of chaotic systems. In addition, we have analyzed several theoretical spectra including the latest lattice QCD calculation. With a single exception, their statistical properties are close to those of a generic integrable system, and thus incompatible with the experimental spectrum. 
L. Munoz, C. Fernandez-Ramirez, A. Relano, J. Retamosa
nucl-th hep-lat hep-ph nucl-ex