IKKT as a nonperturbative formulation of type IIB string theory

Establish that the IKKT matrix model, i.e., ten-dimensional super Yang–Mills theory reduced to zero dimensions with action S_IKKT, furnishes a nonperturbative formulation of type IIB superstring theory.

Background

The paper discusses holography for the extremal p = −1 case, relating the D(−1) instanton background of Euclidean type IIB supergravity to the IKKT matrix model, which is ten-dimensional super Yang–Mills reduced to zero dimensions. The authors recall that the IKKT model has long been proposed as a fundamental description of IIB strings beyond perturbation theory.

They develop a one-dimensional maximal supergravity capturing the lowest Kaluza–Klein sector relevant for holography, setting the stage for precision tests. However, whether IKKT truly provides a complete nonperturbative formulation of type IIB string theory remains an explicit conjecture in the literature.