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arXiv · 1312.5415

A renormalization group method for studying the early universe in the Lorentzian IIB matrix model

Yuta Ito·Sang-Woo Kim·Yuki Koizuka·Jun Nishimura·Asato Tsuchiya
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Abstract

We propose a new method for studying the early universe in the Lorentzian version of the IIB matrix model, which is considered to be a nonperturbative formulation of superstring theory. This method is based on the idea of renormalization group, and it enables us to study the time-evolution of the universe for much longer time than in the previous work, which showed that the SO(9) rotational symmetry is spontaneously broken down to SO(3) after a "critical time". We demonstrate how this method works in a simplified model, which is expected to capture the behaviors of the original model when the space is not so large. In particular, we present clear evidence that the three-dimensional space expands exponentially after the critical time in this simplified model.

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Yuta Ito, Sang-Woo Kim, Yuki Koizuka, Jun Nishimura, Asato Tsuchiya. 2013-12-19. A renormalization group method for studying the early universe in the Lorentzian IIB matrix model. https://doi.org/10.1093/ptep%2Fptu101

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