Article
Astronomy & Astrophysics
Gabriele Bozzola, Vasileios Paschalidis
Summary: Unlike energy and angular momentum, electric charge is conserved in mergers of charged black holes. This paper investigates the formation of naked singularities in quasicircular mergers of charged binary black holes. The theoretical model is extended to estimate the properties of the remnant left by these mergers, and numerical-relativity simulations validate the model's accuracy. The theoretical model suggests that while naked singularities cannot form following these mergers, remnants that are arbitrarily close to the extremal limit can be produced.
Article
Physics, Particles & Fields
Tomas Ortin
Summary: In this study, the toroidal compactification of the Bergshoeff-de Roo version of the Heterotic Superstring effective action to first order in alpha ' was performed. The dimensionally-reduced action was then utilized to derive a manifestly-O(n, n)-invariant Wald entropy formula, which was applied to calculate the entropy of alpha ' -corrected, 4-dimensional, 4-charge, static, extremal, supersymmetric black holes.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Andres Anabalon, Dumitru Astefanesei, Antonio Gallerati, Mario Trigiante
Summary: This article investigates a family of four-dimensional, N = 2 supergravity theories that interpolate between single dilaton truncations of the SO(8) gauged N = 8 supergravity. The study includes constructing non-extremal black hole solutions and their supersymmetric limits, as well as analyzing their effects on the dual theory.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Astronomy & Astrophysics
Zhan-Feng Mai, Run-Qiu Yang, H. Lu
Summary: In this study, we investigate the superradiant (in)stability of extremal multicharge static black holes in the STU supergravity model. We show that the frequency of quasibound states is complex and derive the corresponding superradiant condition. By examining the effective potential of the Schrodinger-like equation, we find trapping-well configurations with either a single peak or double peaks. Numerical calculations reveal the unstable quasibound states and the deviation of charged black holes from the RN black hole. The results indicate that the superradiant stability of extremal RN black hole is a fine-tuning result in the framework of the STU supergravity model.
Article
Astronomy & Astrophysics
S. Cremonini, M. Cvetic, C. N. Pope, A. Saha
Summary: Motivated by recent studies, this research extends the investigation of forces between identical black holes to two nonidentical black holes. The study reveals that nonidentical black holes repel each other, while certain non-extremal nonidentical black holes can satisfy a zero-force condition.
Article
Physics, Multidisciplinary
Ankit Aggarwal, Alejandra Castro, Stephane Detournay, Beatrix Muhlmann
Summary: A holographic description of three-dimensional warped black holes encounters ambiguities arising from the choice of coordinate system. This study focuses on two ensembles, namely the canonical and quadratic ensembles. By investigating the thermodynamic response and evaluating greybody factors, the authors quantify the effects of these ensembles in the near-extremal limit of a warped black hole. They also establish a holographic dictionary in the near-AdS2 region and decipher aspects of the dual nearCFT1. The results show perfect agreement between the near-extremal limit of the canonical ensemble warped black holes, their near-AdS2 effective analysis, and a warped conformal field theory description, while ruling out the quadratic ensemble due to inconsistencies at the quantum level with the near-AdS2 effective description.
Article
Astronomy & Astrophysics
Kushal Chakraborty, Suvankar Dutta
Summary: In this study, invariants for a class of knots and links in arbitrary representations in S-3/Z(p) were computed in the large k, large N limit in U(N) and Sp(N) Chern-Simons theories. The results for the Hopf link and unknot invariants were found to be related to collective field theory, and were used to compute invariants for other torus knots and links. The phase structure of the Hopf link invariant in the large N limit was discussed, indicating a possible phase transition depending on representations and lambda.
Article
Astronomy & Astrophysics
Antonio Gallerati
Summary: In this study, a special class of N=2 supergravity model that interpolates all the single-dilaton truncations of the maximal SO(8) gauged supergravity is reviewed. Explicit non-extremal, charged black hole solutions, their supersymmetric limits, asymptotic charges, thermodynamics and boundary conditions are provided. Suitable Hamilton-Jacobi formulation and related BPS flow equations for the supersymmetric configurations are discussed, along with an explicit form for the superpotential function. Finally, certain models within the class are briefly analyzed as consistent truncations of the maximal, N=8 gauged supergravity in four dimensions.
Article
Physics, Particles & Fields
Parinya Karndumri
Summary: We have discovered a new class of supersymmetric AdS5 black strings in five-dimensional N=4 gauged supergravity theory coupled to five vector multiplets with SO(2) x SO(3) x SO(3) gauge group. These solutions have near horizon geometries of the form AdS3 x Sigma(2), where Sigma(2) can be a two-sphere (S-2) or a hyperbolic space (H-2). There are four supersymmetric AdS5 vacua with N=4 and N=2 supersymmetries. By performing topological twists along Sigma(2) with SO(2) x SO(2) diag and SO(2) diag gauge fields, we find a number of AdS(3) x Sigma(2) fixed points describing near horizon geometries of black strings in asymptotically AdS(5) spaces. Most of the solutions take the form of AdS(3) x H-2, with only one preserving SO(2) diag symmetry, AdS(3) x S-2. We also provide the corresponding black string solutions that interpolate between asymptotically locally AdS(5) vacua and the near horizon AdS(3) x Sigma(2) geometries. There exist solutions flowing from one, two, or three AdS(5) vacua to an AdS3 x Sigma(2) fixed point. These solutions can be considered as holographic RG flows across dimensions from N=2 and N=1 SCFTs in four dimensions to two-dimensional SCFTs with N=(2, 0) or N=(0, 2) supersymmetry.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Astronomy & Astrophysics
Tomohiro Harada, Chul-Moon Yoo, Kazunori Kohri, Yasutaka Koga, Takeru Monobe
Summary: The study estimates the standard deviation of the nondimensional Kerr parameter of primordial black holes formed in the radiation-dominated phase of the universe, showing a relationship between the probability of PBH formation and the standard deviation of spins as well as the width of the power spectrum. It also highlights a numerical comparability between the first-order and second-order effects.
ASTROPHYSICAL JOURNAL
(2021)
Article
Physics, Particles & Fields
Shuxuan Ying
Summary: By introducing an extra flat spatial direction and using the O(d, d) rotation with the special Kalb-Ramond field, the singularity of the three-dimensional black string can be resolved and the known potentials for the loop corrections fail to regulate the singularity issue.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Astronomy & Astrophysics
David Matejov, Jiri Podolsky
Summary: In this paper, we generalize our previous work on the geometry of axially symmetric extremal isolated horizons in asymptotically flat spacetime to include EIHs in asymptotically (anti-)de Sitter spacetime. The resulting metric depends on several parameters and is consistent with results obtained in the context of near-horizon geometries. We also study the extremal horizons of all black holes within the Plebanski-Demianski exact (electro)vacuum spacetimes of the algebraic type D, and identify the corresponding extremal horizons for the Kerr-Newman-NUT-(A)dS metric, including their position and geometry.
Article
Physics, Particles & Fields
Brett McInnes
Summary: The article discusses the application of the Weak Gravity Conjecture in holography, which predicts a lower bound on the density of cold strongly coupled matter through gauge-gravity duality.
Article
Astronomy & Astrophysics
Sebastian Murk
Summary: The existence of black holes is crucial for testing the consistency of general relativity and modified gravity theories. Only two types of dynamic solutions in spherical symmetry are compatible with the formation of an apparent horizon. Properties of f(R) and generic fourth-order gravity theories naturally fit both types of solutions. Observations of an apparent horizon alone may not be sufficient to distinguish between general relativity and modifications with up to fourth-order derivatives in the metric.
Article
Physics, Particles & Fields
Mangesh Mandlik
Summary: This study examines the solutions of stationary black rings in Einstein-Maxwell theory with or without cosmological constant within the framework of the large D membrane paradigm. It is shown that the first order membrane equations only allow for static asymptotically flat black rings, and the equilibrium angular velocity for asymptotically AdS black rings at large D is obtained. The thermodynamic and dynamic stability of the asymptotically flat black ring solutions is also investigated, with arguments that the apparent shortcomings of some results can be addressed within the large D membrane paradigm framework.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Multidisciplinary
Sergio Ferrara, Augusto Sagnotti
FORTSCHRITTE DER PHYSIK-PROGRESS OF PHYSICS
(2016)
Article
Physics, Particles & Fields
S. Ferrara, A. Sagnotti, A. Yeranyan
Editorial Material
Astronomy & Astrophysics
Sergio Ferrara, Massimo Porrati
Article
Astronomy & Astrophysics
N. Cribiori, G. Dall'Agata, F. Farakos, M. Porrati
Article
Physics, Particles & Fields
M. J. Duff, S. Ferrara, A. Marrani
JOURNAL OF HIGH ENERGY PHYSICS
(2017)
Article
Physics, Particles & Fields
N. Cribiori, G. Dall'Agata, F. Farakos
JOURNAL OF HIGH ENERGY PHYSICS
(2017)
Article
Astronomy & Astrophysics
Gianguido Dall'Agata
Article
Physics, Particles & Fields
Sergio Ferrara, Dieter Lust
JOURNAL OF HIGH ENERGY PHYSICS
(2018)
Article
Physics, Multidisciplinary
Sergio Ferrara, Marine Samsonyan, Magnus Tournoy, Antoine Van Proeyen
FORTSCHRITTE DER PHYSIK-PROGRESS OF PHYSICS
(2018)
Article
Physics, Particles & Fields
Sergio Ferrara, Alex Kehagias, Dieter Lust
JOURNAL OF HIGH ENERGY PHYSICS
(2018)
Article
Physics, Particles & Fields
Niccolo Cribiori, Gianguido Dall'Agata
JOURNAL OF HIGH ENERGY PHYSICS
(2018)
Article
Physics, Particles & Fields
Sergio Ferrara, Alex Kehagias, Dieter Lust
JOURNAL OF HIGH ENERGY PHYSICS
(2019)
Article
Physics, Particles & Fields
Gianguido Dall'Agata, Gianluca Inverso, Paolo Spezzati
JOURNAL OF HIGH ENERGY PHYSICS
(2019)
Proceedings Paper
Physics, Multidisciplinary
S. Ferrara, A. Marrani, A. Yeranyan
FUTURE OF OUR PHYSICS INCLUDING NEW FRONTIERS
(2017)
Article
Astronomy & Astrophysics
Sergio Ferrara, Renata Kallosh, Jesse Thaler
Article
Physics, Particles & Fields
Bogdan Damski
Summary: In this paper, we discuss the dynamics of field configurations in the Proca theory of the real massive vector field, specifically focusing on a certain class of electric (magnetic) dipole-charged states. We construct these states to ensure that the long-distance structure of the mean electromagnetic field is initially set by the formula describing the electromagnetic field of the electric (magnetic) dipole. We analyze the evolution of this mean electromagnetic field over time and observe the phenomena of harmonic oscillations of the electric (magnetic) dipole moment far from the center of the initial field configuration, as well as the emergence of a spherical shock wave propagating at the speed of light near the center. Additionally, we discover a unique axisymmetric mean electric field configuration accompanying the mean magnetic field in magnetic dipole-charged states.
Article
Physics, Particles & Fields
Brett McInnes
Summary: The time-dependence of AdS black hole interior geometries poses challenges to holographic duality and the traversability of wormholes. Quantum circuit complexity of strongly coupled matter can address the first challenge. Data from a phenomenological model show an upper bound on the complexity growth rate, which becomes stricter with the addition of angular momentum. The slowing of black hole interior dynamics at high specific angular momentum also occurs.
Article
Physics, Particles & Fields
M. Beccaria, S. Giombi, A. A. Tseytlin
Summary: This article investigates the superconformal index Z of the 6d (2,0) theory on S5 x S1 and describes it using the quantum M2 brane theory in the large N limit. By studying M2 branes in a twisted product of thermal AdS7 and S4, the leading non-perturbative term at large N is shown to be reproduced by the 1-loop partition function of an instanton M2 brane wrapped on S1 x S2 with S2 c S4. Similarly, the partition function of a defect M2 brane wrapped on thermal AdS3 c AdS7 reproduces the BPS Wilson loop expectation value in the (2,0) theory. The article also comments on the analogy of these results with similar computations in the quantum M2 brane partition function in AdS4 x S7/DOUBLE-STRUCK CAPITAL Zk, which reproduced the corresponding localization expressions in the ABJM 3d gauge theory.
Article
Physics, Particles & Fields
Carlos Silva
Summary: This paper explores the nature of spacetime in quantum gravity based on a new version of the holographic principle that establishes a connection between string theory and polymer holonomy structures. The research findings suggest that, for this relationship to hold, spacetime must be perceived as emerging from a fundamental structure with degrees of freedom corresponding to quantum correlations only.
Article
Physics, Particles & Fields
A. Senol, H. Denizli, C. Helveci
Summary: This study investigates new physics using a Monte Carlo method, and the results show stronger limitations on anomalous quartic gauge couplings compared to previous experiments.
