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arXiv · 2307.01681

The emergence of expanding space-time in the Lorentzian type IIB matrix model with a novel regularization

Mitsuaki Hirasawa·Konstantinos N. Anagnostopoulos·Takehiro Azuma·Kohta Hatakeyama·Jun Nishimura·Stratos 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 recently found that a Euclidean space-time appears in the conventional large-$N$ limit. In this work, we study the model with a Lorentz invariant mass term which can be considered as an IR regulator. By performing complex Langevin simulations to overcome the sign problem, we observe the emergence of expanding space-time with Lorentzian signature.

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Mitsuaki Hirasawa, Konstantinos N. Anagnostopoulos, Takehiro Azuma, Kohta Hatakeyama, Jun Nishimura, Stratos Papadoudis, Asato Tsuchiya. 2023-07-04. The emergence of expanding space-time in the Lorentzian type IIB matrix model with a novel regularization. https://arxiv.org/abs/2307.01681

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