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arXiv · 1108.0058

Summing Planar Diagrams by an Integrable Bootstrap

Peter Orland
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Abstract

Correlation functions of matrix-valued fields are not generally known for massive renormalized field theories. We find the large-N limit of form factors of the (1+1)-dimensional sigma model with SU(N) X SU(N) symmetry. These form factors give a correction to the free-field approximation for the N=infinity Wightman function. The method is a combination of the 1/N-expansion of the S-matrix and Smirnov's form-factor axioms. We expand the renormalized field in terms of a free massive Bosonic field as N goes to infinity.

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Peter Orland. 2011-07-30. Summing Planar Diagrams by an Integrable Bootstrap. https://doi.org/10.1103/physrevd.84.105005

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