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arXiv · hep-th/0411019

Matrix Model and Time-like Linear Dilaton Matter

Tadashi Takayanagi
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Abstract

We consider a matrix model description of the 2d string theory whose matter part is given by a time-like linear dilaton CFT. This is equivalent to the c=1 matrix model with a deformed, but very simple fermi surface. Indeed, after a Lorentz transformation, the corresponding 2d spacetime is a conventional linear dilaton background with a time-dependent tachyon field. We show that the tree level scattering amplitudes in the matrix model perfectly agree with those computed in the world-sheet theory. The classical trajectories of fermions correspond to the decaying D-branes in the time-like linear dilaton CFT. We also discuss the ground ring structure. Furthermore, we study the properties of the time-like Liouville theory by applying this matrix model description. We find that its ground ring structure is very similar to that of the minimal string.

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Tadashi Takayanagi. 2005-04-04. Matrix Model and Time-like Linear Dilaton Matter. https://doi.org/10.1088/1126-6708%2F2004%2F12%2F071

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