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arXiv · hep-th/0312021

Non-perturbative RR Potentials in the c=1 Matrix Model

David J. Gross·Johannes Walcher
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Abstract

We use the \hat c=1 matrix model to compute the potential energy V(C) for (the zero mode of) the RR scalar in two-dimensional type 0B string theory. The potential is induced by turning on a background RR flux, which in the matrix model corresponds to unequal Fermi levels for the two types of fermions. Perturbatively, this leads to a linear runaway potential, but non-perturbative effects stabilize the potential, and we find the exact expression V(C)=\frac{1}{2π}\int da\arccos [\cos(C)/\sqrt{1+e^{-2πa}}]. We also compute the finite-temperature partition function of the 0B theory in the presence of flux. The perturbative expansion is T-dual to the analogous result in type 0A theory, but non-perturbative effects (which depend on C) do not respect naive R\to 1/R duality. The model can also be used to study scattering amplitudes in background RR fluxes.

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David J. Gross, Johannes Walcher. 2003-12-01. Non-perturbative RR Potentials in the c=1 Matrix Model. https://doi.org/10.1088/1126-6708%2F2004%2F06%2F043

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