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On the Emerging Phenomenology of <(A_μ)^2>

F. V. Gubarev·V. I. Zakharov
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Abstract

We discuss phenomenology of the vacuum condensate <(A_μ)^2> in pure gauge theories, where A_μis the gauge potential. Both Abelian and non-Abelian cases are considered. In case of the compact U(1) the non-perturbative part of the condensate <(A_μ)^2> is saturated by monopoles. In the non-Abelian case, a two-component picture for the condensate is presented according to which finite values of order Λ_{QCD}^2 are associated both with large and short distances. We obtain a lower bound on the <(A_μ)^2> by considering its change at the phase transition. Numerically, it produces an estimate similar to other measurements. Possible physical manifestations of the condensate are discussed.

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F. V. Gubarev, V. I. Zakharov. 2000-10-10. On the Emerging Phenomenology of <(A_μ)^2>. https://doi.org/10.1016/s0370-2693(01)00085-5

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