Weyl consistency conditions in non-relativistic quantum field theory

Relativistic Quantum Field Theory

Electromagnetic Interaction of Anyons in Non-relativistic Quantum Field Theory

The non-relativistic quantum field theoretic lagrangian which describes an anyon system in the presence of an electromagnetic field is identified. A non-minimal magnetic coupling to the Chern-Simons statistical field as well as to the electromagnetic field together with a direct coupling between both fields are the non trivial ingredients of the lagrangian obtained from the non relativistic lim...

Quasiparticle excitations in relativistic quantum field theory

We analyze the particle-like excitations arising in relativistic field theories in states different than the vacuum. The basic properties characterizing the quasiparticle propagation are studied using two different complementary methods. First we introduce a frequency-based approach, wherein the quasiparticle properties are deduced from the spectral analysis of the twopoint propagators. Second,...

Unstable Systems in Relativistic Quantum Field Theory

We show how the state of an unstable particle can be defined in terms of stable asymptotic states. This general definition is used to discuss and to solve some old problems connected with the short-time and large-time behaviour of the non-decay amplitude. CERN-TH/97-246 September 1997 ⋆ Address from Sept 1st, 1997 to August 31st, 1998.

8.324 Relativistic Quantum Field Theory II

The renormalization program has been shown to be a success operationally: 1. For a renormalizable theory, all ultraviolet divergences can be absorbed into redefinitions of bare quan­ tities, which are not observable. What is meant by the set of physical observables is unambiguous: it is well-defined in terms of a small number of physical couplings, masses and so forth. 2. The requirement of ren...