Comments on Penrose Limit of AdS_4 x M^{1,1,1}

TL;DR

This paper constructs a Penrose limit of AdS_4 x M^{1,1,1} that matches the pp-wave geometry of AdS_4 x S^7, revealing a supersymmetry enhancement in a specific gauge theory sector.

Contribution

It demonstrates a Penrose limit of AdS_4 x M^{1,1,1} leading to a pp-wave geometry and identifies the supersymmetry enhancement in the dual gauge theory.

Findings

Matching pp-wave geometries for different backgrounds

Identification of operators with supergravity excitations

Supersymmetry enhancement in a gauge theory subsector

Abstract

We construct a Penrose limit of AdS_4 x M^{1,1,1} where M^{1,1,1}= SU(3) x SU(2) x U(1)/(SU(2) x U(1) x U(1)) that provides the pp-wave geometry equal to the one in the Penrose limit of AdS_4 x S^7. There exists a subsector of three dimensional N=2 dual gauge theory which has enhanced N=8 maximal supersymmetry. We identify operators in the N=2 gauge theory with supergravity KK excitations in the pp-wave geometry and describe how the gauge theory operators made out of two kinds of chiral fields of conformal dimension 4/9, 1/3 fall into N=8 supermultiplets.