Parity doubling of highly excited mesons

Glozman has proposed that highly excited mesons and baryons fall into parity doublets, and that the f4(2050) on the leading Regge trajectory should have a nearly degenerate J^{PC} = 4^{-+} partner. A re-analysis of Crystal Barrel data does not support this idea. A likely explanation is that centrifugal barriers on the leading trajectory allow formation of the L=J-1 states, but are too strong to allow L=J states. Two new polarisation experiments have the potential for major progress in meson spectroscopy.