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arXiv · hep-th/0311068

The Cap in the Hat: Unoriented 2D Strings and Matrix(-Vector) Models

Oren Bergman·Shinji Hirano
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Abstract

We classify the possible bosonic and Type 0 unoriented string theories in two dimensions, and find their dual matrix(-vector) models. There are no RP^2 R-R tadpoles in any of the models, but many of them possess a massless tachyon tadpole. Thus all the models we find are consistent two-dimensional string vacua, but some get quantum corrections to their classical tachyon background. Where possible, we solve the tadpole cancellation condition, and find all the tachyon tadpole-free theories.

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Oren Bergman, Shinji Hirano. 2003-11-19. The Cap in the Hat: Unoriented 2D Strings and Matrix(-Vector) Models. https://doi.org/10.1088/1126-6708%2F2004%2F01%2F043

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