On consistent truncations in N = 2* holography

Abstract

Although Pilch-Warner (PW) gravitational renormalization group flow [1] passes a number of important consistency checks to be identified as a holographic dual to a large-N SU(N) N = 2* supersymmetric gauge theory, it fails to reproduce the free energy of the theory on S4, computed with the localization techniques. This disagreement points to the existence of a larger dual gravitational consistent truncation, which in the gauge theory flat-space limit reduces to a PW flow. Such truncation was recently identified by Bobev-Elvang-Freedman-Pufu (BEFP) [2]. Additional bulk scalars of the BEFP gravitation truncation might lead to destabilization of the finite-temperature deformed PW flows, and thus modify the low-temperature thermodynamics and hydrodynamics of N = 2* plasma. We compute the quasinormal spectrum of these bulk scalar fields in the thermal PW flows and demonstrate that these modes do not condense, as long as the masses of the N = 2* hypermultiplet components are real.