Entropy of Monopoles from Percolating Cluster in Quenched Su(2) Qcd *

The dual superconductor picture [1] of the QCD vacuum is based on the existence of Abelian monopoles which appear naturally in an Abelian gauge. There are various indications that the monopoles are responsible for the color confinement (for a review, see Ref. [2]). One of the most important results is the observation of the monopole condensate in the confinement phase [3,4]. The monopole trajectories form clusters. Typically, each lattice configuration contains many finite-sized (ultraviolet) clusters and one large percolating (infrared) cluster [5,6,7]. The IR cluster – which occupies the whole lattice – represents the monopole condensate [5]. The tension of the confining string gets a dominant contribution from the IR cluster [6]. In the deconfinement phase the IR cluster disappears [5,6], as expected. The UV and IR monopole clusters were studied previously in Refs. [6,7,8,9,10]. Below we investigate the action and length distribution of the infrared monopole cluster for various lattice sizes and scales b at which the magnetic charge is defined. Using the action and length distribution we investigate the entropy of the IR clusters.