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arXiv · hep-th/9708051

Gluon Condensation in Nonperturbative Flow Equations

M. Reuter·C. Wetterich
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Abstract

We employ nonperturbative flow equations for an investigation of the effective action in Yang-Mills theories. We compute the effective action $Γ[B]$ for constant color magnetic fields $B$ and examine Savvidy's conjecture of an unstable perturbative vacuum. Our results indicate that the absolute minimum of $Γ[B]$ occurs for B=0. Gluon condensation is described by a nonvanishing expectation value of the regularized composite operator $F_{μν}F^{μν}$ which agrees with phenomenological estimates.

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M. Reuter, C. Wetterich. 1997-08-09. Gluon Condensation in Nonperturbative Flow Equations. https://doi.org/10.1103/physrevd.56.7893

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