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arXiv · hep-th/9407014

A modified c=1 matrix model with new critical behavior

Steven S. Gubser·Igor R. Klebanov
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Abstract

By introducing a $\int dt \, g\left(\Tr Φ^2(t)\right)^2$ term into the action of the $c=1$ matrix model of two-dimensional quantum gravity, we find a new critical behavior for random surfaces. The planar limit of the path integral generates multiple spherical ``bubbles'' which touch one another at single points. At a special value of $g$, the sum over connected surfaces behaves as $Δ^2 \logΔ$, where $Δ$ is the cosmological constant (the sum over surfaces of area $A$ goes as $A^{-3}$). For comparison, in the conventional $c=1$ model the sum over planar surfaces behaves as $Δ^2/ \logΔ$.

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Steven S. Gubser, Igor R. Klebanov. 1994-07-05. A modified c=1 matrix model with new critical behavior. https://doi.org/10.1016/0370-2693(94)91294-7

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