Dilatonic states near holographic phase transitions

Abstract

The spectrum of bound states of special strongly coupled confining field theories might include a parametrically light dilaton, associated with the formation of enhanced condensates that break (approximate) scale invariance spontaneously. It has been suggested in the literature that such a state may arise in connection with the theory being close to the unitarity bound in holographic models. We extend these ideas to cases where the background geometry is non-AdS, and the gravity description of the dual confining field theory has a top-down origin in supergravity. We exemplify this programme by studying the circle compactification of Romans six-dimensional half-maximal supergravity. We uncover a rich space of solutions, many of which were previously unknown in the literature. We compute the bosonic spectrum of excitations, and identify a tachyonic instability in a region of parameter space for a class of regular background solutions. A tachyon only exists along an energetically disfavoured (unphysical) branch of solutions of the gravity theory; we find evidence of a first-order phase transition that separates this region of parameter space from the physical one. Along the physical branch of regular solutions, one of the lightest scalar particles is approximately a dilaton, and it is associated with a condensate in the underlying theory. Yet, because of the location of the phase transition, its mass is not parametrically small, and it is, coincidentally, the next-to-lightest scalar bound state, rather than the lightest one.

Version accepted for publication

References in corpus (19)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• Light scalar at LHC: the Higgs or the dilaton?
• Lectures on Gauged Supergravity and Flux Compactifications
• A Light Dilaton in Walking Gauge Theories
• Glueballs vs. Gluinoballs: Fluctuation Spectra in Non-AdS/Non-CFT
• Phenomenology of a light scalar: the dilaton
• Extending Chiral Perturbation Theory with an Isosinglet Scalar
• Stability of strings dual to flux tubes between static quarks in N=4 SYM
• Light scalars from a compact fifth dimension
• Fate of false vacua in holographic first-order phase transitions
• Effective pion mass term and the trace anomaly
• Holographic Modelling of a Light Techni-Dilaton
• S-parameter, Technimesons, and Phase Transitions in Holographic Tachyon DBI Models
• Holographic line defects in F(4) gauged supergravity
• The $\epsilon$-regime of dilaton chiral perturbation theory
• A Higgs Impostor in Low-Scale Technicolor
• Effective field theory for pions and a dilatonic meson
• Examining the Low Energy Dynamics of Walking Gauge Theory

Cited by in corpus (7)

• Holographic description of SCFT${}_5$ compactifications
• Spectra of glueballs and oddballs and the equation of state from holographic QCD
• Toward minimal composite Higgs models from regular geometries in bottom-up holography
• The Coulomb branch of N=4 SYM and dilatonic scions in supergravity
• Phase transitions and light scalars in bottom-up holography
• Multiple Mass Hierarchies from Complex Fixed Point Collisions
• Light dilaton near critical points in top-down holography