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arXiv · 2212.10127

The emergence of expanding space-time in a novel large-$N$ limit of the Lorentzian type IIB matrix model

Mitsuaki Hirasawa·Konstantinos N. Anagnostopoulos·Takehiro Azuma·Kohta Hatakeyama·Jun Nishimura·Stratos Kovalkov Papadoudis·Asato Tsuchiya
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Abstract

The Lorentzian type IIB matrix model is a promising candidate for a non-perturbative formulation of superstring theory. However, it was found recently that a Euclidean space-time appears in the conventional large-$N$ limit. In this work, we add a Lorentz invariant mass term to the original model and consider a limit, in which the coefficient of the mass term vanishes at large $N$. By performing complex Langevin simulations to overcome the sign problem, we observe the emergence of expanding space-time with the Lorentzian signature.

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Mitsuaki Hirasawa, Konstantinos N. Anagnostopoulos, Takehiro Azuma, Kohta Hatakeyama, Jun Nishimura, Stratos Kovalkov Papadoudis, Asato Tsuchiya. 2022-12-20. The emergence of expanding space-time in a novel large-$N$ limit of the Lorentzian type IIB matrix model. https://arxiv.org/abs/2212.10127

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