Vacua of M theory and string theory

Vacua of M-theory and String Theory

We argue that supersymmetric higher-dimension operators in the effective actions of M-theory and IIB string theory do not affect the maximally supersymmetric vacua: adS4 × S 7 and adS7 × S 4 in Mtheory and adS5 × S 5 in IIB string theory. All these vacua are described in superspace by a fixed point with all components of supertorsion and supercurvature being supercovariantly constant. This foll...

The statistics of string/M theory vacua

We discuss systematic approaches to the classification of string/M theory vacua, and physical questions this might help us resolve. To this end, we initiate the study of ensembles of effective Lagrangians, which can be used to precisely study the predictive power of string theory, and in simple examples can lead to universality results. Using these ideas, we outline an approach to estimating th...

Statistics of supersymmetric vacua in string/M theory

DEVELOPMENT IN STRING THEORY

The string theory is a fast moving subject, both physics wise and in the respect of mathematics. In order to keep up with the discipline it is important to move with new ideas which are being stressed. Here I wish to give extracts from new papers of ideas which I have recently found interesting. There are six papers which are involved: I ."Strings formulated directly in 4 dimensions " A. N...

Flux-vacua in Two Dimensional String Theory

We analyze the two dimensional type 0 theory with background RR-fluxes. Both the 0A and the 0B theory have two distinct fluxes q and q̃. We study these two theories at finite temperature (compactified on a Euclidean circle of radius R) as a function of the fluxes, the tachyon condensate μ and the radius R. Surprisingly, the dependence on q, q̃ and μ is rather simple. The partition function is the...