The transverse structure of the QCD string

Understand

The characterization of the transverse structure of the QCD string is discussed.

• We formulate a conjecture as to how the stress-energy tensor of the underlying gauge theory couples to the string degrees of freedom.
• A consequence of the conjecture is that the energy density and the longitudinal-stress operators measure the distribution of the transverse position of the string, to leading order in the string fluctuations, whereas the transverse-stress operator does not.
• We interpret recent numerical measurements of the transverse size of the confining string and show that the difference of the energy and longitudinal-stress operators is the appropriate probe to use when comparing with the next-to-leading order string prediction.