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arXiv · hep-th/9309100

Critical scaling in the matrix model on the Bethe tree

D. Boulatov
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Abstract

The matrix model with a Bethe-tree embedding space (coinciding at large $N$ with the Kazakov-Migdal ``induced QCD'' model \cite{KM}) is investigated. We further elaborate the Riemann-Hilbert approach of \rf{Mig1} assuming certain holomorphic properties of the solution. The critical scaling (an edge singularity of the density) is found to be $γ_{str} = -\frac{1}π \arcos D$, for $|D|<1$, and $γ_{str} = -\frac{1}π \arcos \frac{D}{2D-1}$, for $D>1$. Explicit solutions are constructed at $D=\frac{1}{2}$ and $D=\infty$.

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D. Boulatov. 1993-09-18. Critical scaling in the matrix model on the Bethe tree. https://doi.org/10.1142/s0217732394001829

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