Effective Action and Measure in Matrix Model of IIB Superstrings

TL;DR

This paper computes the effective action and measure in a matrix model for IIB superstrings, showing the measure's uniqueness and properties in the large-N limit, with implications for continuum limits.

Contribution

It provides a detailed calculation of the induced measure in a matrix model for IIB superstrings, highlighting its ultralocal nature and invariance properties.

Findings

The measure is uniquely determined by locality and reparametrization invariance.

In the large-N limit, the measure becomes ultralocal.

The model's relation to the GKM type is discussed.

Abstract

We calculate an effective action and measure induced by the integration over the auxiliary field in the matrix model recently proposed to describe IIB superstrings. It is shown that the measure of integration over the auxiliary matrix is uniquely determined by locality and reparametrization invariance of the resulting effective action. The large--$N$ limit of the induced measure for string coordinates is discussed in detail. It is found to be ultralocal and, thus, possibly is irrelevant in the continuum limit. The model of the GKM type is considered in relation to the effective action problem.