Dynamical generation of hyperon resonances

In this talk we report on how, using a chiral unitary approach for the meson-baryon interactions, two octets of Jπ=1/2− baryon states and a singlet are generated dynamically, resulting in the case of strangeness S=−1 in two poles of the scattering matrix close to the nominal Λ(1405) resonance. We suggest experiments which could show evidence for the existence of these states.