Parity Doublets in the Baryon Spectrum
نویسندگان
چکیده
Physics of the low-lying and high-lying hadrons in the light flavors sector is reviewed. While the low-lying hadrons are strongly affected by both U(1) A and spontaneous SU(2) L × SU(2) R breakings, in the high-lying hadrons these symmetries are restored. A manifestation is a persistence of the chiral multiplet structure in both baryon and meson spectra. A fundamental origin of this phenomenon is that effects of quantum fluctuations of both quark and gluon fields must vanish at large n or J and a semiclassical description becomes adequate. A relation between the chiral symmetry restoration and the string picture of excited hadrons is discussed.
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