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arXiv · hep-th/0003223

Spontaneous Breakdown of Lorentz Invariance in IIB Matrix Model

J. Nishimura·G. Vernizzi
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Abstract

We study the IIB matrix model, which is conjectured to be a nonperturbative definition of superstring theory, by introducing an integer deformation parameter `nu' which couples to the imaginary part of the effective action induced by fermions. The deformed IIB matrix model continues to be well-defined for arbitrary `nu', and it preserves gauge invariance, Lorentz invariance, and the cluster property. We study the model at `nu' = infinity using a saddle-point analysis, and show that ten-dimensional Lorentz invariance is spontaneously broken at least down to an eight-dimensional one. We argue that it is likely that the remaining eight-dimensional Lorentz invariance is further broken, which can be checked by integrating over the saddle-point configurations using standard Monte Carlo simulation.

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J. Nishimura, G. Vernizzi. 2000-05-01. Spontaneous Breakdown of Lorentz Invariance in IIB Matrix Model. https://doi.org/10.1088/1126-6708%2F2000%2F04%2F015

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