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IR Renormalisation of General Effective Actions and Hawking Flux in 2D Gravity Theories

D. Hofmann·W. Kummer
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Abstract

The infrared problem of the effective action in 2D is discussed in the framework of the Covariant Perturbation Theory. The divergences are regularised by a mass and the leading term is evaluated up to the third order of perturbation theory. A summation scheme is proposed which isolates the divergences from the finite part of the series and results in a single term. The latter turns out to be equivalent to the coupling to a certain classical external field. This suggests a renormalisation by factorisation.

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D. Hofmann, W. Kummer. 2005-12-29. IR Renormalisation of General Effective Actions and Hawking Flux in 2D Gravity Theories. https://doi.org/10.1140/epjc%2Fs2006-02553-3

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