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arXiv · 0705.2140

Tree-Level Stability Without Spacetime Fermions: Novel Examples in String Theory

Dan Israel·Vasilis Niarchos
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Abstract

Is perturbative stability intimately tied with the existence of spacetime fermions in string theory in more than two dimensions? Type 0'B string theory in ten-dimensional flat space is a rare example of a non-tachyonic, non-supersymmetric string theory with a purely bosonic closed string spectrum. However, all known type 0' constructions exhibit massless NSNS tadpoles signaling the fact that we are not expanding around a true vacuum of the theory. In this note, we are searching for perturbatively stable examples of type 0' string theory without massless tadpoles in backgrounds with a spatially varying dilaton. We present two examples with this property in non-critical string theories that exhibit four- and six-dimensional Poincare invariance. We discuss the D-branes that can be embedded in this context and the type of gauge theories that can be constructed in this manner. We also comment on the embedding of these non-critical models in critical string theories and their holographic (Little String Theory) interpretation and propose a general conjecture for the role of asymptotic supersymmetry in perturbative string theory.

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Dan Israel, Vasilis Niarchos. 2007-07-28. Tree-Level Stability Without Spacetime Fermions: Novel Examples in String Theory. https://doi.org/10.1088/1126-6708%2F2007%2F07%2F065

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