We construct new families of type-IIB supergravity solutions by employing TsT transformations on the ten-dimensional geometry that arises after the uplift of the five-dimensional soliton solution of Anabalón, Nastase, and Oyarzo. In particular, we identify two marginal and two dipole deformations of the uplifted geometry. We then analyse a plethora of holographic observables — including Wilson loops, ‘t Hooft loops, Page charges, entanglement entropy, and central charge — and compare their behaviour across the different deformed backgrounds.

United Kingdom

Madison Hammond

Germany

Georgios Itsios

Holographic observables in TsT deformations of confining theories

We construct solutions of type-II supergravity based on multiple copies and/or mixings of $\textit{λ}$-deformed coset CFTs on $$ \frac{\textrm{SO}{\left(n+1\right)}_k}{\textrm{SO}{(n)}_k} $$ , with $\textit{n}$ = 2, 3, 4. The resulting ten-dimensional geometries contain undeformed AdS factors, thereby allowing a connection between $\textit{λ}$-deformations and the AdS/CFT correspondence. Imposing reality conditions on the solutions further constrains the deformation parameter. In some cases these bounds exclude the undeformed ($\textit{λ}$ = 0) or non-Abelian T-dual ($\textit{λ}$ → 1) limits. This work extends the results of arXiv:1911.12371 and arXiv:2411.11086.

Giuseppe Casale

Supergravity realisations of λ-models

This work, which accompanies [1], is about constructing smooth solutions in type II and eleven dimensional supergravity which describe supersymmetry preserving RG flows from four-dimensional SCFTs in the UV to three-dimensional SQFTs in the IR, through holography. We show that all the different UV fixed points flow to theories which confine external quarks and have a mass gap. We proceed by presenting extended calculations of a plethora of observables and analyse the dual field theories in great detail. This includes a boundary analysis and application of holographic renormalization methods in the simplest case of the type IIB solution. Many of the observables computed here have a universal behaviour: they factorize into two parts, one of which includes information about the UV SCFTs, and the other describing the dynamics of the RG flow, which is the same regardless of the UV fixed point.

Dimitrios Chatzis

Carlos Nunez

Greece

Dimitrios Zoakos

Supersymmetric AdS solitons, Coulomb branch flows and twisted compactifications

We construct the integrable $\textit{λ}$-model on SU(3) $\textit{/}$U(2) and we compute the one-loop $\textit{β}$-function for the deformation parameter $\textit{λ}$. Its non-compact version, corresponding to the coset SU(2$\textit{,}$ 1) $\textit{/}$U(2) is also considered. The target space of the latter admits an asymptotic region that can be reached when one of the coordinates becomes large. The asymptotic model can be seen as an integrable deformation of the SU(2) $\textit{/}$U(1) WZW model together with a linear dilaton and a free boson, where integrability is inherited from the parental $\textit{λ}$-model. By taking an asymptotic double-scaling limit of the SU(2$\textit{,}$ 1) $\textit{/}$U(2) model, we obtain a two-dimensional field theory that is scale-invariant but not conformally invariant at one-loop order. Crucially, this deformation does not admit a Kerr-Schild form, unlike the cases studied in arXiv:2109.05040. However, in a suitable asymptotic regime, scale invariance is enhanced to full conformal invariance. Finally, we construct Type-II supergravity embeddings of the asymptotic model for specific values of the deformation parameter.

Konstantinos Siampos

Scale without conformal invariance from integrable deformations of coset CFTs

We construct and analyse infinite classes of regular supergravity backgrounds dual to four-dimensional superconformal field theories (SCFTs) compactified on a circle with a supersymmetry-preserving twist. These flows lead to three-dimensional gapped QFTs preserving four supercharges. The solutions arise in Type IIB, Type IIA, and eleven-dimensional supergravity, and generalise known constructions by incorporating deformations that avoid typical singularities associated with the holographic description of the Coulomb branch of the CFT. We examine several observables: Wilson loops, holographic central charges, and complexity. We show they exhibit a universal factorisation, with each observable decomposing into a UV-CFT contribution times a flow-dependent factor. We also explore the parameter regimes where higher-curvature corrections become relevant, affecting the physical interpretation of certain observables. Our findings provide new insights into universal features of holographic RG flows and resolve a puzzle related to complexity in these systems.

Universal observables, SUSY RG-flows and holography

We construct a plethora of type-II supergravity solutions featuring AdS factors in their geometries, derived from integrable deformations of coset CFTs. Specifically, we uplift the $\textit{λ}$-deformed models of SO(4) $\textit{/}$SO(3) and SO(5) $\textit{/}$SO(4) , including the non-compact version of the latter. Requiring reality for the backgrounds imposes bounds on the deformation parameter. As a result, some of the solutions do not admit non-Abelian T-dual limit.

Type-II backgrounds from deformed coset CFTs

We construct a generalisation of the -deformation of the Principal Chiral Model (PCM) where we deform just a subgroup of the full symmetry group . We find that demanding Lax integrability imposes a crucial restriction, namely that the coset must be symmetric. Surprisingly, we also find that (when is non-abelian) integrability requires that the term in the action involving only the spectator fields should have a specific -dependence, which is a curious modification of the procedure expected from the known = case. The resulting Lax connection has a novel analytical structure, with four single poles as opposed to the two poles of the cases of the PCM and of the standard -deformation. We also explicitly work out the example of = SU(2) and = U(1), discussing its renormalisation group flow to two loops.

Spain

Riccardo Borsato

J. Miramontes

Integrability of the

We construct the embedding of the λ-model on SL(2, ℝ) × SU(2) × SU(2) in type-II supergravity. In the absence of deformation, the ten-dimensional background corresponds to the near-horizon limit of the NS1-NS5-NS5 brane intersection. We show that when the deformation is turned on, supersymmetry breaks by half, and the solution preserves 8 supercharges. The Penrose limits along two null geodesics of the deformed geometry are also considered. It turns out that none of the associated plane-wave backgrounds exhibit supernumerary supercharges.

Supersymmetric solutions of type-II supergravity from λ-deformations and zoom-in limits

We provide the first supersymmetric embedding of an integrable λ-deformation to type-II supergravity. Specifically, that of the near horizon of the NS1-NS5 brane intersection, geometrically corresponding to AdS 3 × S 3 × T 4. We show that the deformed background preserves 1/4 of the maximal supersymmetry. In the Penrose limit we show that it preserves no-more than one half of the maximal supersymmetry.

Konstantinos Sfetsos

Supersymmetric backgrounds from λ-deformations

We generalize the Mellin representation for a generic co-dimension flat defect CFT. We study the analytic structure of the Mellin amplitudes. We also compute Witten diagrams for a generic co-dimension flat defect CFT.