Stability of the Matrix Model in Operator Interpretation

TL;DR

This paper investigates the stability of the IIB matrix model interpreted as a differential operator on a principal bundle, revealing mass generation for certain fields and implications for nonperturbative string theory.

Contribution

It demonstrates the necessity of principal bundles for stability and diffeomorphism invariance, and computes one-loop corrections showing mass generation in the matrix model.

Findings

Mass terms are generated for some fields due to loop corrections.

Supersymmetry breaking occurs while original massless fields remain unaffected.

A new mass scale emerges through quantum corrections.

Abstract

The IIB matrix model is one of the candidates for nonperturbative formulation of string theory, and it is believed that the model contains gravitational degrees of freedom in some manner. In some preceding works, it was proposed that the matrix model describes the curved space where the matrices represent differential operators that are defined on a principal bundle. In this paper, we study the dynamics of the model in this interpretation, and point out the necessity of the principal bundle from the viewpoint of the stability and diffeomorphism invariance. We also compute the one-loop correction which possibly yields a mass term for each field due to the principal bundle. We find that the correction does generate some mass terms with the supersymmetry broken, while fields in the original IIB matrix model remain massless. The positivity is not violated as long as the number of bosonic degrees of freedom is larger than the fermionic counterpart. The generation of mass terms means that the new mass scale emerges through the loop correction.