Multiscale confining dynamics from holographic RG flows

Abstract

We consider renormalization group flows between conformal field theories in five (six) dimensions with a string (M-theory) dual. By compactifying on a circle (torus) with appropriate boundary conditions, we obtain continuous families of confining fourdimensional theories parametrized by the ratio Λ flow /Λ QCD , with Λ flow the scale at which the flow between fixed points takes place and Λ QCD the confinement scale. We construct the dual geometries explicitly and compute the spectrum of scalar bound states (glueballs). We find a 'universal' subset of states common to all the models. We comment on the modifications of these models, and the corresponding fine-tuning, required for a parametrically light 'dilaton' state to be present. We also comment on some aspects of these theories as probed by extended objects such as strings and branes.

Large mass hierarchies from strongly-coupled dynamics

“…These techniques have been applied successfully to the dual of confining gauge theories, such as the Witten model [66][67][68], the Klebanov-Strassler model [61][62][63]69], the MaldacenaNunez model [61-63, 70, 71] and several generalisations, including cases in which the mass of the continuum massless theory. In this paper we collectively call lattice artefacts all effects that are not present in the continuum massless field theory, inclusive of finite volume, finite spacing and finite fermion mass effects.…”

“…In GPPZ [76,78], the asymptotic (in the UV) geometry is AdS 5 × S 5 and R = √ 2. A less known example exists [103] (see also [68]), in which the local geometry is asymptotically AdS 6 × S 4 (one dimension is compactified on a shrinking circle), and for which R ≃ 1.6. In the Witten model [66], the local asymptotic geometry is AdS 7 × S 4 (two dimensions are compactified on shrinking circles), and R ≃ 1.7 [67].…”

New N $$ \mathcal{N} $$ =1 supersymmetric AdS 5 backgrounds in type IIA supergravity

“…A natural question, given the importance of Abelian T-duality, to ask is how can this non-Abelian duality be exploited in the context of holography. Here we will restrict our focus to conformal backgrounds with AdS 5 factors in the geometries (a number of related recent works have considered non-Abelian T-duality in various other contexts [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]). …”

A UV complete compositeness scenario: LHC constraints meet the lattice

“…The field Ψ can be written in terms of its components that have definite quantum numbers under the standard model gauge group SU(3) c × SU(2) × U(1): 8) where the quantum numbers are (T, B) ∈ (3, 2) 1/6 , R ∈ (3, 1) 2/3 , and (X, Y ) ∈ (3, 2) 7/6 . Expanding this Lagrangian yields a mass matrix in the top partner space (t, T, Y, R): 9) and an analogous matrix in the bottom partner space (b, B): 10) where hatted quantities, e.g.M ≡ M/f , are made dimensionless by dividing by the appropriate power of f . In the expressions above c h ≡ cos(ĥ) and s h ≡ sin(ĥ), where h is the…”

“…We find that for such a mass choice the decay into gluons typically dominates. 9 However, it is worthwhile to also check the sensitivity to these states in other final states, also extending beyond the aforementioned diphoton analysis.…”