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arXiv · 2504.06481

Statistical Physics of the Polarised IKKT Matrix Model

Sean A. Hartnoll·Jun Liu
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Abstract

The polarised IKKT matrix model is the worldpoint theory of $N$ D-instantons in a background three-form flux of magnitude $\Omega$, and promises to be a highly tractable model of holography. The matrix integral can be viewed as a statistical physics partition function with inverse temperature $\Omega^4$. At large $\Omega$ the model is dominated by a matrix configuration corresponding to a 'polarised' spherical D1-brane. We show that at a critical value of $\Omega^2 N$ the model undergoes a first order phase transition, corresponding to tunneling into a collection of well-separated D-instantons. These instantons are the remnant of a competing saddle in the high $\Omega$ phase corresponding to spherical $(p,q)$ fivebranes. We use a combination of numerical and analytical arguments to capture the different regimes of the model.

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Sean A. Hartnoll, Jun Liu. 2025-04-08. Statistical Physics of the Polarised IKKT Matrix Model. https://doi.org/10.21468/scipostphys.19.4.099

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