Abstract
We study the thickness of the confining flux tube generated by
a pair of sources in higher representations of the gauge group. Using a simple
geometric picture we argue
that the area of the cross-section of the flux tube, as measured by a
Wilson loop probe, grows logarithmically with source separation, as a
consequence of the quantum fluctuations of the underlying k-string.
The slope of the logarithm turns out to be universal, i.e. it is the same for
all the representations and all the gauge theories. We check these predictions
in a 3D 
4 lattice gauge model by comparing the broadening of the 1-string
and the 2-string.
Export citation and abstract BibTeX RIS