Holographic Theories at Finite θ‐Angle, CP‐Violation, Glueball Spectra and Strong‐Coupling Instabilities

Abstract

A general class of holographic theories with a nontrivial θ‐angle are analyzed. The instanton density operator is dual to a bulk axion field. We calculate the ground‐state solutions with nontrivial source, aUV, for the axion, for both steep and soft dilaton potentials in the IR, and both in d=3 and d=4. We find all cases to be qualitatively similar. We also calculate the spin=2, 0 glueball spectra and show that the glueball masses monotonically decrease as functions of aUV (or θ‐angle). The slopes of glueball masses are different, generically, in different potentials. In the case of steep dilaton potentials, the glueball (masses)2 turn negative before the maximum of aUV is attained. We interpret this as a signal for a favored instanton condensation in the bulk. We also investigate strong CP‐violation in the effective glueball action.

Multifield inflation beyond Nfield=2: non-Gaussianities and single-field effective theory

“…Note that although what one can have in mind is a sufficiently long period of inflation for which both and η = ˙ /(H ) must be small, all the results presented in this paper are exact in the sense that they are not expansions in those parameters, except if explicitly mentioned. In particular, our results are perfectly applicable to the description of transient departures from slow-roll, other attractors such as ultra-slow-roll, or even multi-scalar dynamics beyond inflation (see [59] for a recent application of our previous work [47] in the case of N field = 2 to holographic theories).…”

Holographic QFTs on AdSd, wormholes and holographic interfaces

“…This in turn should translate into the properties of the instanton fluid in the dual gauge theory. For example, in holographic flows connecting AdS vacua, it can be shown in general that even turning a non-trivial θ-angle, the vev of the dual operator vanishes, [57,58]. In the presence of AdS slices, this is not expected to be true anymore.…”

Holographic RG flows on Squashed S3

“…In this context, the holographic dimension serves as an effective RG scale in the dual QFT, thus geometrizing the notion of RG flow. In essence, RG flows can be understood as bulk evolution in the holographic dimensions [32]- [12,54].…”