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arXiv · 2406.16867

Normalization of ZZ instanton amplitudes in type 0B minimal superstring theory

Vivek Chakrabhavi·Dan Stefan Eniceicu·Raghu Mahajan·Chitraang Murdia
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Abstract

We study ZZ instanton corrections in the $(2,4k)$ $N=1$ minimal superstring theory with the type 0B GSO projection, which becomes the type 0B $N=1$ super-JT gravity in the $k \to \infty$ limit. Each member of the $(2,4k)$ family of theories has two phases distinguished by the sign of the Liouville bulk cosmological constant. The worldsheet method for computing the one-loop normalization constant multiplying the instanton corrections gives an ill-defined answer in both phases. We fix these divergences using insights from string field theory and find finite, unambiguous results. Each member of the $(2,4k)$ family of theories is dual to a double-scaled one-matrix integral, where the double-scaling limit can be obtained starting either from a unitary matrix integral with a leading one-cut saddle point, or from a hermitian matrix integral with a leading two-cut saddle point. The matrix integral exhibits a gap-closing transition, which is the same as the double-scaled Gross-Witten-Wadia transition when $k=1$. We also compute instanton corrections in the double-scaled matrix integral for all $k$ and in both phases, and find perfect agreement with the string theory results.

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Vivek Chakrabhavi, Dan Stefan Eniceicu, Raghu Mahajan, Chitraang Murdia. 2024-06-24. Normalization of ZZ instanton amplitudes in type 0B minimal superstring theory. https://arxiv.org/abs/2406.16867

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