We investigate the dual superconductivity hypothesis in pure SU(2) lattice
gauge theory. We focus on the dual Meissner effect by analyzing the
distribution of the color fields due to a static quark-antiquark pair. We find
evidence of the dual Meissner effect both in the maximally Abelian gauge and
without gauge fixing. We measure the London penetration length. Our results
suggest that the London penetration length is a physical gauge-invariant
quantity. We put out a simple relation between the penetration length and the
square root of the string tension. We find that our extimation is quite close
to the extrapolated continuum limit available in the literature. A remarkable
consequence of our study is that an effective Abelian theory can account for
the long range properties of the SU(2) confining vacuum.Comment: 38 pages, uuencoded compressed (using GNU's gzip) tar file containing
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