Nonlinear dynamics in threedimensional QED and nontrivial infrared structure
Abstract
In this work we consider a coupled system of SchwingerDyson equations for selfenergy and vertex functions in QED_{3}. Using the concept of a semiamputated vertex function, we manage to decouple the vertex equation and transform it in the infrared into a nonlinear differential equation of the EmdenFowler type. Its solution suggests the following picture: in the absence of infrared cutoffs there is only a trivial infrared fixedpoint structure in the theory. However, the presence of masses, for either fermions or photons, changes the situation drastically, leading to a massdependent nontrivial infrared fixed point. In this picture a dynamical mass for the fermions is found to be generated consistently. The nonlinearity of the equations gives rise to highly nontrivial constraints among the mass and effective (``running'') gauge coupling, which impose lower and upper bounds on the latter for dynamical mass generation to occur. Possible implications of this to the theory of hightemperature superconductivity are briefly discussed.
 Publication:

Physical Review D
 Pub Date:
 December 1999
 DOI:
 10.1103/PhysRevD.60.125008
 arXiv:
 arXiv:hepth/9904046
 Bibcode:
 1999PhRvD..60l5008M
 Keywords:

 11.15.Me;
 11.10.Kk;
 11.15.Tk;
 Strongcoupling expansions;
 Field theories in dimensions other than four;
 Other nonperturbative techniques;
 High Energy Physics  Theory;
 Condensed Matter;
 High Energy Physics  Phenomenology
 EPrint:
 29 pages LATEX, 7 eps figures incorporated, uses axodraw style. Discussion on the massless case (section 2) modified