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The Gluon Propagator in Minkowski and Euclidean Space: Role of an A^2 Condensate

Xiangdong Li C. M. Shakin
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Abstract

In a recent work we described the form taken by the Minkowski-space gluon propagator in the presence of an A^2 condensate. This condensate has been seen to play an important role in calculations which make use of the operator product expansion. The latter work has led to the publication of a large number of papers which discuss how the A^2 condensate could play a role in a gauge-invariant formulation. In the present work we discuss the properties of both the Euclidean-space and Minkowski-space gluon propagator. In the case of the Euclidean-space propagator we can make contact with the results of QCD lattice calculations of the propagator in the Landau gauge. With an appropriate choice of normalization constants, we present a unified representation of the gluon propagator that describes both the Minkowski-space and Euclidean-space dynamics in which the A^2 condensate plays an important role.

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Xiangdong Li C. M. Shakin. 2004-11-18. The Gluon Propagator in Minkowski and Euclidean Space: Role of an A^2 Condensate. https://arxiv.org/abs/hep-ph/0411234

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