Effective Field Theory in Nuclear Physics
Date : June 13, 2001 16:00 ~
Speaker : Dr. Kuniharu Kuboder(Univ. of South Carolina)
Professor :
Location : 56동106호
EFFECTIVE FIELD THEORY IN NUCLEAR PHYSICS
Kuniharu Kubodera
Department of Physics and Astronomy, University of South Carolina,
Columbia, SC 29208, USA
Nuclear physics applications of effective field theory (EFT) are steadily gaining ground for certain classes of nuclear observables.
Primary motivations for nuclear EFT are two-fold:
(1) It provides a long sought link between conventional nuclear physics and QCD;
(2) Its accuracy can be monitored systematically in a well-defined expansion scheme.
The basic idea of EFT is simple. For phenomena characterized by an energy momentum scale of order $Q$, we only need to consider light particles with masses $m \lsim Q$ as explicit degrees of freedom. The effects of heavy particles are subsumed in the coefficients of an infinite series of monomials of the light-particle fields, and this series is controlled by the expansion parameter $Q/\Lambda$, where $\Lambda$ is a typical mass scale of the heavy particles. By determining the coefficients of this series (up to a specified order of expansion) using empirical inputs, we arrive at the most general Lagrangian consistent with the symmetries of the system, a Lagrangian that allows us to make model-independent predictions. I wish to discuss the working of nuclear EFT as applied to electroweak observables in few-body systems.
Kuniharu Kubodera
Department of Physics and Astronomy, University of South Carolina,
Columbia, SC 29208, USA
Nuclear physics applications of effective field theory (EFT) are steadily gaining ground for certain classes of nuclear observables.
Primary motivations for nuclear EFT are two-fold:
(1) It provides a long sought link between conventional nuclear physics and QCD;
(2) Its accuracy can be monitored systematically in a well-defined expansion scheme.
The basic idea of EFT is simple. For phenomena characterized by an energy momentum scale of order $Q$, we only need to consider light particles with masses $m \lsim Q$ as explicit degrees of freedom. The effects of heavy particles are subsumed in the coefficients of an infinite series of monomials of the light-particle fields, and this series is controlled by the expansion parameter $Q/\Lambda$, where $\Lambda$ is a typical mass scale of the heavy particles. By determining the coefficients of this series (up to a specified order of expansion) using empirical inputs, we arrive at the most general Lagrangian consistent with the symmetries of the system, a Lagrangian that allows us to make model-independent predictions. I wish to discuss the working of nuclear EFT as applied to electroweak observables in few-body systems.