Complex-mass renormalization in chiral effective field theory

Renormalization and Effective Field Theory

One-Nucleon Effective Generators of the Poincaré Group derived from a Field Theory: Mass Renormalization

We start from a Lagrangian describing scalar ”nucleons” and mesons which interact through a simple vertex. Okubo’s method of unitary transformation is used to describe a single nucleon dressed by its meson cloud. We find an expression for the physical mass of the nucleon being correct up to second order in the coupling constant. It is then verified that this result is the same as the correspond...

On the Renormalization of Heavy Quark Effective Field Theory

The construction of heavy quark effective field theory (HqEFT) is extended to arbitrary order in both expansion parameters αs and 1/mq. Matching conditions are discussed for the general case, and it is verified that this approach correctly reproduces the infrared behaviour of full QCD. Choosing a renormalization scheme in the full theory fixes the renormalization scheme in the effective theory ...

Electromagnetic nucleon-to-delta transition in chiral effective-field theory.

We perform a relativistic chiral effective-field theory calculation of pion electroproduction off the nucleon (e- N --> e- N(pi)) in the delta(1232)-resonance region. After fixing the three low-energy constants, corresponding to the magnetic (M1), electric (E2), and Coulomb (C2) gammaNdelta couplings, our calculation provides a prediction for the momentum transfer and pion-mass dependence of th...

Effective Field Theory of pure Gravity and the Renormalization Group

The general structure of the renormalization group equations for the low energy effective field theory formulation of pure gravity is presented. The solution of these equations takes a particular simple form if the mass scale of the effective theory is much smaller than the Planck mass (a possibility compatible with the renormalization of the effective theory). A theory with just one free renor...