Acena, A., Anabalon, A., & Astefanesei, D. (2013). Exact hairy black brane solutions in 5D antide Sitter space and holographic renormalization group flows. Phys. Rev. D, 87(12), 6 pp.
Abstract: We construct a general class of exact regular black hole solutions with toroidal horizon topology in fivedimensional antide Sitter gravity with a selfinteracting scalar field. With these boundary conditions and due to the nontrivial backreaction of the scalar field, the nohair theorems can be evaded so that an event horizon can be formed. The scalar field is regular everywhere outside the curvature singularity and it vanishes at the boundary where the potential is finite. We study the properties of these black holes in the context ofAdS/CFT duality and comment on the dual operators, which saturate the unitarity bound. We present exact expressions for the beta function and construct a cfunction that characterizes the renormalizationgroup flow.

Acena, A., Anabalon, A., Astefanesei, D., & Mann, R. (2014). Hairy planar black holes in higher dimensions. J. High Energy Phys., (1), 21 pp.
Abstract: We construct exact hairy planar black holes in Ddimensional AdS gravity. These solutions are regular except at the singularity and have stressenergy that satisfies the null energy condition. We present a detailed analysis of their thermodynamical properties and show that the first law is satisfied. We also discuss these solutions in the context of AdS/CFT duality and construct the associated cfunction.

Anabalon, A., & Astefanesei, D. (2014). Black holes in omegadeformed gauged N=8 supergravity. Phys. Lett. B, 732, 137–141.
Abstract: Motivated by the recently found 4dimensional omegadeformed gauged supergravity, we investigate the black hole solutions within the single scalar field consistent truncations of this theory. We construct black hole solutions that have spherical, toroidal, and hyperbolic horizon topologies. The scalar field is regular everywhere outside the curvature singularity and the stressenergy tensor satisfies the null energy condition. When the parameter CO does not vanish, there is a degeneracy in the spectrum of black hole solutions for boundary conditions that preserve the asymptotic Antide Sitter symmetries. These boundary conditions correspond to multitrace deformations in the dual field theory. (C) 2014 The Authors. Published by Elsevier B.V.

Anabalon, A., & Astefanesei, D. (2013). On attractor mechanism of AdS(4) black holes. Phys. Lett. B, 727(45), 568–572.
Abstract: We construct a general family of exact nonextremal 4dimensional black holes in AdS gravity with U(1) gauge fields nonminimally coupled to a dilaton and a nontrivial dilaton potential. These black holes can have spherical, toroidal, and hyperbolic horizon topologies. We use the entropy function formalism to obtain the near horizon data in the extremal limit. Due to the nontrivial selfinteraction of the scalar field, the zero temperature black holes can have a finite horizon area even if only the electric field is turned on. (C) 2013 Elsevier B.V. All rights reserved.

Anabalon, A., Astefanesei, D., & Choque, D. (2016). Hairy AdS solitons. Phys. Lett. B, 762, 80–85.
Abstract: We construct exact hairy AdS soliton solutions in Einsteindilaton gravity theory. We examine their thermodynamic properties and discuss the role of these solutions for the existence of first order phase transitions for hairy black holes. The negative energy density associated to hairy AdS solitons can be interpreted as the Casimir energy that is generated in the dual filed theory when the fermions are antiperiodic on the compact coordinate. (C) 2016 Published by Elsevier B.V.

Anabalon, A., Astefanesei, D., & Choque, D. (2015). On the thermodynamics of hairy black holes. Phys. Lett. B, 743, 154–159.
Abstract: We investigate the thermodynamics of a general class of exact 4dimensional asymptotically Antide Sitter hairy black hole solutions and show that, for a fixed temperature, there are small and large hairy black holes similar to the SchwarzschildAdS black hole. The large black holes have positive specific heat and so they can be in equilibrium with a thermal bath of radiation at the Hawking temperature. The relevant thermodynamic quantities are computed by using the Hamiltonian formalism and counterterm method. We explicitly show that there are first order phase transitions similar to the HawkingPage phase transition. (C) 2015 The Authors. Published by Elsevier B.V.

Anabalon, A., Astefanesei, D., Choque, D., & Martinez, C. (2016). Trace anomaly and counterterms in designer gravity. J. High Energy Phys., (3), 29 pp.
Abstract: We construct concrete counterterms of the BalasubramanianKraus type for Einsteinscalar theories with designer gravity boundary conditions in AdS(4), so that the total action is fi nite onshell and satisfy a well de fi ned variational principle. We focus on scalar fi elds with the conformal mass m(2) = 2l(2) and show that the holographic mass matches the Hamiltonian mass for any boundary conditions. We compute the trace anomaly of the dual fi eld theory in the generic case, as well as when there exist logarithmic branches of nonlinear origin. As expected, the anomaly vanishes for the boundary conditions that are AdS invariant. When the anomaly does not vanish, the dual stress tensor describes a thermal gas with an equation of state related to the boundary conditions of the scalar fi eld. In the case of a vanishing anomaly, we recover the dual theory of a massless thermal gas. As an application of the formalism, we consider a general family of exact hairy black hole solutions that, for some particular values of the parameters in the moduli potential, contains solutions of fourdimensional gauged N = 8 supergravity and its omegadeformation. Using the AdS/CFT duality dictionary, they correspond to triple trace deformations of the dual fi eld theory.

Anabalon, A., Astefanesei, D., & Mann, R. (2017). Holographic equation of state in fluid/gravity duality. Phys. Lett. B, 770, 272–277.
Abstract: We establish a precise relation between mixed boundary conditions for scalar fields in asymptotically anti de Sitter spacetimes and the equation of state of the dual fluid. We provide a detailed derivation of the relation in the case of five bulkdimensions for scalar fields saturating the BreitenlohnerFreedman bound. As a concrete example, we discuss the five dimensional scalartensor theories describing dark energy in four dimensions. (C) 2017 Published by Elsevier B.V.

Anabalon, A., Astefanesei, D., & Mann, R. (2013). Exact asymptotically flat charged hairy black holes with a dilaton potential. J. High Energy Phys., (10), 22 pp.
Abstract: We find broad classes of exact 4dimensional asymptotically flat black hole solutions in EinsteinMaxwell theories with a nonminimally coupled dilaton and its nontrivial potential. We consider a few interesting limits, in particular, a regular generalization of the dilatonic ReissnerNordstrom solution and, also, smooth deformations of supersymmetric black holes. Further examples are provided for more general dilaton potentials. We discuss the thermodynamical properties and show that the first law is satisfied. In the nonextremal case the entropy depends, as expected, on the asymptotic value of the dilaton. In the extremal limit, the entropy is determined purely in terms of charges and is independent of the asymptotic value of the dilaton. The attractor mechanism can be used as a criterion for the existence of the regular solutions. Since there is a 'competition' between the effective potential and dilaton potential, we also obtain regular extremal black hole solutions with just one U(1) gauge field turned on.

Anabalon, A., Astefanesei, D., & Martinez, C. (2015). Mass of asymptotically antide Sitter hairy spacetimes. Phys. Rev. D, 91(4), 6 pp.
Abstract: In the standard asymptotic expansion of fourdimensional static asymptotically flat spacetimes, the coefficient of the first subleading term of the lapse function can be identified with the mass of the spacetime. Using the Hamiltonian formalism we show that, in asymptotically locally antide Sitter spacetimes endowed with a scalar field, the mass can read off in the same way only when the boundary conditions are compatible with the asymptotic realization of the antide Sitter symmetry. Since the mass is determined only by the spatial metric and the scalar field, the above effect appears by considering not only the constraints, but also the dynamic field equations, which relate the spatial metric with the lapse function. In particular, this result implies that some prescriptions for computing the mass of a hairy spacetime are not suitable when the scalar field breaks the asymptotic antide Sitter invariance.

Anabalon, A., Astefanesei, D., & Oliva, J. (2015). Hairy black hole stability in AdS, quantum mechanics on the halfline and holography. J. High Energy Phys., (10), 15 pp.
Abstract: We consider the linear stability of 4dimensional hairy black holes with mixed boundary conditions in Antide Sitter spacetinie. We focus on the mass of scalar fields around the maximally supersymmetric vacuum of the gauged N = 8 supergravity in four dimensions, m(2) = 2l(2). It is shown that the Schrodinger operator on the halfline, governing the S2, H2 or R2 invariant mode around the hairy black hole, allows for nontrivial selfadjoint extensions and each of them corresponds to a class of mixed boundary conditions in the gravitational theory. Discarding the selfadjoint extensions with a negative mode impose a restriction on these boundary conditions. The restriction is given in terms of an integral of the potential in the Schrodinger operator resembling the estimate of Simon for Schrodinger operators on the real line. In the context of AdS/CFT duality, our result has a natural interpretation in terms of the field theory dual effective potential.
