Low-energy pion-nucleon scattering

Several topics in pion-nucleon scattering at low energies are addressed. First, we review the predictions of chiral symmetry for the near-threshold region. The pion-nucleon scattering lengths and the Cheng-Dashen theorem with the related issue of the strangeness content of the nucleon are discussed in some detail. Finally, the status of the scalar mesons and the relevance of the pomeron and the concept of duality for pion-nucleon dynamics is pointed out.Lecture given at the 8th Summer School on Intermediate Energy Physics: Hadron Dynamics at Low and Intermediate Energies, Prague, July 10–14, 1995.I would like to thank the organizers of the Praha Indian-summer school for inviting me to this beautiful city. I am indebted to Th. Rijken and J. J. de Swart for discussions about the pomeron, the scalar mesons, and partial-wave analysis, and to U. van Kolck and J. Friar for discussions about chiral symmetry. This work was included in the research program of the Stichting voor Fundamenteel Onderzoek der Materie (FOM) with financial support from the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO).