Exact $m_{quark}\neq 0$ Condensates in $QCD_{1+1}(N_C\rightarrow \infty)$
Abstract
Description
In the limit of an infinite number of colors, we derive an analytic expression for the quark condensate in $QCD_{1+1}$ as a function of the quark mass and the gauge coupling constant. For zero quark mass, a nonvanishing quark condensate is obtained. Nevertheless, we prove that there is no phase transition as a function of the quark mass. It is furthermore shown that the expansion of $\langle 0 | \overlineψψ|0\rangle$ in the gauge coupling has zero radius of convergence but that the perturbation series is Borel summable with finite radius of convergence. The nonanalytic behavior $\langle 0 | \overlineψψ|0\rangle \stackrel{m_q\rightarrow0}{\sim} - N_C \sqrt{G^2}$ can only be obtained by summing the perturbation series to infinite order.
5 pages, 1 postscript figure (available by email from the author), LATEX
5 pages, 1 postscript figure (available by email from the author), LATEX