{ "id": "math-ph/0309042", "version": "v2", "published": "2003-09-17T19:49:52.000Z", "updated": "2004-04-19T20:40:12.000Z", "title": "Algebraic Approach to the 1/N Expansion in Quantum Field Theory", "authors": [ "Stefan Hollands" ], "comment": "52 pages, Latex, 4 figures, includes self-contained review of the operator algebraic approach to perturbatively defined quantum field theory in Minkowski spacetime, updated version", "journal": "Rev.Math.Phys. 16 (2004) 509", "doi": "10.1142/S0129055X04002072", "categories": [ "math-ph", "math.MP" ], "abstract": "The 1/N expansion in quantum field theory is formulated within an algebraic framework. For a scalar field taking values in the $N$ by $N$ hermitian matrices, we rigorously construct the gauge invariant interacting quantum field operators in the sense of power series in 1/N and the `t Hooft coupling parameter as members of an abstract *-algebra. The key advantages of our algebraic formulation over the usual formulation of the 1/N expansion in terms of Green's functions are (i) that it is completely local so that infra-red divergencies in massless theories are avoided on the algebraic level and (ii) that it admits a generalization to quantum field theories on general Lorentzian curved spacetimes. We expect that our constructions are also applicable in models possessing local gauge invariance such as Yang-Mills theories. The 1/N expansion of the renormalization group flow is constructed on the algebraic level via a family of *-isomorphisms between the algebras of interacting field observables corresponding to different scales. We also consider $k$-parameter deformations of the interacting field algebras that arise from reducing the symmetry group of the model to a diagonal subgroup with $k$ factors. These parameters smoothly interpolate between situations of different symmetry.", "revisions": [ { "version": "v2", "updated": "2004-04-19T20:40:12.000Z" } ], "analyses": { "subjects": [ "81T15", "81T05" ], "keywords": [ "quantum field theory", "algebraic approach", "gauge invariant interacting quantum field", "invariant interacting quantum field operators", "models possessing local gauge invariance" ], "tags": [ "journal article" ], "publication": { "journal": "Reviews in Mathematical Physics", "year": 2004, "volume": 16, "number": 4, "pages": 509 }, "note": { "typesetting": "LaTeX", "pages": 52, "language": "en", "license": "arXiv", "status": "editable", "inspire": 628534, "adsabs": "2004RvMaP..16..509H" } } }