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arXiv · 1103.1089

Fluid Membranes and 2d Quantum Gravity

A. Codello·O. Zanusso
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Abstract

We study the RG flow of two dimensional (fluid) membranes embedded in Euclidean D-dimensional space using functional RG methods based on the effective average action. By considering a truncation ansatz for the effective average action with both extrinsic and intrinsic curvature terms we derive a system of beta functions for the running surface tension, bending rigidity and Gaussian rigidity. We look for non-trivial fixed points but we find no evidence for a crumpling transition at $T\neq0$. Finally, we propose to identify the $D\rightarrow 0$ limit of the theory with two dimensional quantum gravity. In this limit we derive new beta functions for both cosmological and Newton's constants.

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A. Codello, O. Zanusso. 2011-08-23. Fluid Membranes and 2d Quantum Gravity. https://doi.org/10.1103/physrevd.83.125021

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