# The 39th International Symposium on Lattice Field Theory (Lattice 2022)

Aug 8 – 13, 2022
Hörsaalzentrum Poppelsdorf
Europe/Berlin timezone

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

Aug 11, 2022, 11:30 AM
20m
CP1-HSZ/1st-1.001 - HS5 (CP1-HSZ)

### CP1-HSZ/1st-1.001 - HS5

#### CP1-HSZ

50
Oral Presentation Theoretical Developments and Applications beyond Particle Physics

### Speaker

Dr Mitsuaki Hirasawa (Istituto Nazionale di Fisica Nucleare (INFN))

### Description

The Lorentzian type IIB matrix model is a promising candidate for a nonperturbative 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 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.

### Primary author

Dr Mitsuaki Hirasawa (Istituto Nazionale di Fisica Nucleare (INFN))

### Co-authors

Prof. Asato Tsuchiya (Shizuoka University) Prof. Jun Nishimura (KEK) Dr Kohta Hatakeyama (KEK) Prof. Konstantinos Anagnostopoulos (National Technical University of Athens) Mr Stratos Papadoudis (National Technical University of Athens) Prof. Takehiro Azuma (Setsunan University)