Scaling similarity and generalised conformal symmetry in D2-brane holography

We study D2-brane holography within the purely dilatonic sector of four-dimensional maximal ISO(7)-gauged supergravity, obtained as a consistent truncation of type IIA supergravity on S${}^6$. In the dual frame, the four-dimensional Lagrangian resulting from the reduction of the massless IIA theory exhibits scaling similarity, thus reflecting the generalised conformal symmetry of the dual three-dimensional maximally supersymmetric Yang-Mills theory. Using an auxiliary spacetime construction, we show that the holographic CFT${}_3$ fixed points and RG-flows known in the massive IIA theory have natural counterparts in the massless IIA theory: QFT${}_3$s with generalised conformal symmetry connected by generalised RG-flows, which we construct numerically. We also revisit the Coulomb branch solutions and propose an extension of Gubser’s singularity criterion to supergravity theories exhibiting scaling similarity.