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arXiv · hep-th/9503172

String Beta Function Equations From c=1 Matrix Model

Avinash Dhar·Gautam Mandal·Spenta R. Wadia
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Abstract

We derive the $σ$-model tachyon $β$-function equation of 2-dimensional string theory, in the background of flat space and linear dilaton, working entirely within the $c=1$ matrix model. The tachyon $β$-function equation is satisfied by a \underbar{nonlocal} and \underbar{nonlinear} combination of the (massless) scalar field of the matrix model. We discuss the possibility of describing the `discrete states' as well as other possible gravitational and higher tensor backgrounds of 2-dimensional string theory within the $c=1$ matrix model. We also comment on the realization of the $W$-infinity symmetry of the matrix model in the string theory. The present work reinforces the viewpoint that a nonlocal (and nonlinear) transform is required to extract the space-time physics of 2-dimensional string theory from the $c=1$ matrix model.

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Avinash Dhar, Gautam Mandal, Spenta R. Wadia. 1995-07-24. String Beta Function Equations From c=1 Matrix Model. https://doi.org/10.1016/0550-3213(95)00319-n

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