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Dispersion relations for the self-energy in non-commutative field theories

F. T. Brandt·Ashok Das·J. Frenkel
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Abstract

We study the IR/UV connection in non-commutative $ϕ^{3}$ theory as well as in non-commutative QED from the point of view of the dispersion relation for the self-energy. We show that, although the imaginary part of the self-energy is well behaved as the parameter of non-commutativity vanishes, the real part becomes divergent as a consequence of the high energy behavior of the dispersion integral. Some other interesting features that arise from this analysis are also briefly discussed.

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F. T. Brandt, Ashok Das, J. Frenkel. 2002-06-07. Dispersion relations for the self-energy in non-commutative field theories. https://doi.org/10.1103/physrevd.66.065017

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