[en] Models for extracting the nucleon resonance parameters from the data of meson-baryon reactions are reviewed. The development of a dynamical coupled-channel model with nnN unitarity is briefly reported

[en] The author reports on several extensions of the Bonn meson exchange model for the NN interaction, first, to the region above pion threshold; second, to systems involving strange particles. 13 refs.; 9 figs

[en] A method to identify hadronic molecules in the particle spectrum is reviewed and the conditions for its applicability discussed. Special emphasis is put on the discussion of molecule candidates in the baryon spectrum. (orig.)

[en] The properties of a relativistic meson-baryon P-wave amplitude subject to a single attractive driving pole are given, and various stability effects are studied

[en] The authors question the viability of the proposed interpretation I = 0, 1/2, and 1 pseudoscalar-pseudoscalar scattering data given in Ref.[1] since t-channel forces have been ignored in apparent conflict with the data in the closely related exotic I = 3/2 and 2 channels

No abstract available

[en] The neutron star parameters in the model extended by the inclusion of δ meson and additional nonlinear vector meson interactions are studied

[en] We discuss some of the most relevant non-standard quark configurations in hadron spectroscopy, which are alternative to the qqq and qq¯ description of baryons and mesons, respectively. They include the quark-diquark and four-quark (five-quark) meson-meson (meson-baryon) bound states. To this purpose, we briefly review the diquark model of baryons and tetraquark states and the hadro-quarkonium model of heavy-light tetra- and pentaquarks. Some applications of the previous models are discussed. (author)

[en] We review the dynamical model for meson-meson scattering developed by our group. This model is based on the meson-exchange picture and reproduces quantitatively the ππ and Kπ phase shifts. These results can be used for the calculation of the pion electromagnetic form factor as well as the scalar factor of the pion. We also discuss our recent calculation of the nucleon sigma term within the same model. (authors)

[en] A scalar field theory with a χ†χφ interaction is known to be unstable. Yet it has been used frequently without any sign of instability in standard text book examples and research articles. In order to reconcile these seemingly conflicting results, we show that the theory is stable if the Fock space of all intermediate states is limited to a finite number of χ| χ loops associated with field χ that appears quadradically in the interaction, and that instability arises only when intermediate states include these loops to all orders