`Chiral Perturbation Theory at Finite Density'

por Jose Antonio Oller (Forschungszentrum Juelich, Alemania)

martes 3 jul. 2001 12:30 → 13:30 Europe/Madrid

Sala Seminarios IFIC (Edf. Institutos de Investigación)

The effective chiral SU(2) Lagrangians with external sources are given in the presence of non-vanishing nucleon density by working out the contributions from the chiral \pi N Lagrangians. As a by product, many-particle quantum field theory at zero temperature is directly derived from relativistic quantum field theory. As applications of the previous formalism we will calculate up to an including next-to-leading order in-medium: quark condensates, pion propagation, vector-axial and pseudoscalar pion transition amplitudes, pi^0->\gamma \gamma, pion scattering and discuss the range of validity of the perturbative expansion. The inclusion in the effective field theory of two or more nucleon contact interactions is beyond the scope of the present work.