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Instability in scalar channel of fermion-antifermion scattering amplitude in massless QED_3 and anomalous dimensions of composite operators

Indrajit Mitra·Raghunath Ratabole·H. S. Sharatchandra
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Abstract

Instability in the scalar channel of the fermion-antifermion scattering amplitude in massless QED_3 for number of flavours less than the critical value 128/3π^2 is demonstrated. The anomalous dimensions of gauge-invariant composite operators are determined to O(1/N). Exponentiation of the O(1/N) infrared logarithm is explicitly demonstrated by evaluating the contribution of the ladder diagrams.

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Indrajit Mitra, Raghunath Ratabole, H. S. Sharatchandra. 2007-01-12. Instability in scalar channel of fermion-antifermion scattering amplitude in massless QED_3 and anomalous dimensions of composite operators. https://doi.org/10.1142/s0217732307020981

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