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.Comment: 10 pages, 8 figures, Contribution to the 39th International Symposium
on Lattice Field theory (LATTICE2022), 8th-13th August, 2022, Bonn, Germany;
(v2) reference adde