Kerr-Newman black holes in a de Sitter (dS) space have the limit of rotating Nariai black holes with the near-horizon geometry of a warped <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>dS</mi><mn>3</mn></msub><mo>×</mo><msup><mi mathvariant="normal">S</mi><mn>1</mn></msup><mo>/</mo><msub><mi>Z</mi><mn>2</mn></msub></math> when the black hole horizon and the cosmological horizon coincide or approach close to each other. We study the rotation effect on the spontaneous emission of charges in the near-extremal rotating charged Nariai black hole and compare it to those from the near-extremal Nariai black hole in [C.-M. Chen et al., <a href="http://dx.doi.org/10.1103/PhysRevD.110.085020">Phys. Rev. D 110, 085020 (2024)</a>] and near-extremal Kerr-Newman black hole in de Sitter space in [C.-M. Chen and S. P. Kim, <a href="http://dx.doi.org/10.1140/epjc/s10052-023-11380-7">Eur. Phys. J. C 83, 219 (2023)</a>]. In strong contrast to the near-extremal Kerr-Newman black hole in dS space, the near-extremal rotating Nariai black hole also has an exponential amplification for the emission of high-energy charges, which becomes catastrophic regardless of angular momentum when two horizons coincide. The radius of rotating Nariai black holes monotonically increases as the angular momentum and charge of black holes increase, which gives a weaker electric field on the horizon than Nariai black holes. Thus, the angular momentum of black holes that drags particles on the horizon decreases the mean number of charges by a factor not by an order. We observe a catastrophic emission of boson condensation for charges with an effective energy equal to the chemical potential in the spacelike outer region of the cosmological horizon. Remarkably, the Schwinger emission of charges in the standard particle model may prevent the rotating Nariai black holes from evolving into spacetimes with a naked singularity when the angular momentum is close to the allowed maximum, which Nariai black holes cannot avoid.

Taiwan

Chiang-Mei Chen

Chun-Chih Huang

South Korea

Sang Pyo Kim

Chun-Yu Wei

Catastrophic emission of charges from near-extremal charged Nariai black holes. II. Rotation effect

Using both the in-out formalism and the monodromy method, we study the emission of charges from near-extremal charged Nariai black holes with the black hole event and cosmological horizons close to each other, whose near-horizon geometry is <math><msub><mi>dS</mi><mn>2</mn></msub><mo>×</mo><msup><mi>S</mi><mn>2</mn></msup></math>. The emission becomes catastrophic for a charge with energy greater than its chemical potential, whose leading exponential factor increases inversely proportional to the separation of two horizons. This effect may prevent near-extremal Nariai black holes with large charges that evaporate dominantly through the charge emission from evolving to black holes with a naked singularity, in analog to near-extremal RN-dS black holes that have the Breitenlohner-Friedman bound, below which they become stable against Hawking radiation and Schwinger effect of charge emission. The near-extremal Nariai black holes with small charges, which are close to near-extremal Schwarzschild-de Sitter black holes, emit dominantly charge-neutral particles and evolve to black holes with increasing charge to mass ratio. We illuminate the origin of the catastrophic emission in the phase-integral formulation and monodromy method by comparing near-extremal charged Nariai black holes with near-extremal Reissner-Nordtröm-dS black holes.

Germany

Catastrophic emission of charges from near-extremal Nariai black holes

We introduce a gravitational lattice theory defined in an <math><mrow><msub><mrow><mi>AdS</mi></mrow><mrow><mn>3</mn></mrow></msub></mrow></math> black hole background that provides a holographic dual description of the linear-to-zigzag structural phase transition, characterized by the spontaneous breaking of parity symmetry observed in, e.g., confined Coulomb crystals. The transition from the high-symmetry linear phase to the broken-symmetry doubly degenerate zigzag phase can be driven by quenching the coupling between adjacent sites through the critical point. An analysis of the equilibrium correlation length and relaxation time reveals mean-field critical exponents. We explore the nonequilibrium phase transition dynamics leading to kink formation. The kink density obeys universal scaling laws in the limit of slow quenches, described by the Kibble-Zurek mechanism (KZM), and at fast quenches, characterized by a universal breakdown of the KZM.

China

Chuan-Yin Xia

Hua-Bi Zeng

Luxembourg

Spain

Adolfo del Campo

Structural phase transition and its critical dynamics from holography

Abstract The open N = 2 string theory is defined on the 4D space-time with the split signature (+, +, −, −). The string field theory action of the open N = 2 string theory is described by the 4D Wess–Zumino–Witten (WZW$_{4}$) model. The equation of motion of the WZW$_{4}$ model is the Yang equation, which is equivalent to the anti-self-dual Yang–Mills equation. In this paper, we study soliton-type classical solutions of the WZW$_{4}$ model in the split signature by calculating the action density of the WZW$_{4}$ model. We find that the action density of the one-soliton solutions is localized on a 3D hyperplane. This shows that there would be codimension-one-solitonic objects, or equivalently some kind of three-branes in the open N = 2 string theory. We also prove that, in the asymptotic region of the space-time, the action density of the n-soliton solutions is a “non-linear superposition” of n one-solitons. This suggests the existence of n intersecting three-branes in the N = 2 strings. Finally we make a reduction to a (1 + 2)D real space-time to calculate the energy densities of the soliton solutions. We can successfully evaluate the energy distribution for the two-soliton solutions and find that there is no singularity in the interacting region. This implies the existence of smooth intersecting codimension-one branes in the whole region. Soliton solutions in the Euclidean signature are also discussed.

Japan

Masashi Hamanaka

Shan-Chi Huang

Hiroaki Kanno

Solitons in open = 2 String Theory Kahler-Chen-Simons theory A tour through N=2 strings On soliton solutions of the anti-self-dual Yang-Mills equations from the perspective of integrable systems Soliton solutions in an integrable chiral model in 2+1 dimensions On the space-time monopole equation A review on tachyon condensation in open string field theories Soliton equations as dynamical systems on infinite dimensional Grassmann manifold

Using the enhanced symmetry in the near-horizon region of the near-extremal dyonic Kerr–Newman (KN) black hole in the (A)dS space, we find the exact solutions for dyonic charged scalar field in terms of the hypergeometric function and explicitly compute the Schwinger effect for the emission of electric and/or magnetic charges. The emission formula confirms a universal factorization of the Schwinger formula in the AdS $$_2$$ <math> <msub> <mrow></mrow> <mn>2</mn> </msub> </math> and another Schwinger formula in the two-dimensional Rindler space determined by the effective temperature and the Hawking temperature with the chemical potentials of electric and/or magnetic charges and the angular momentum. The emission of the same species of charges from the KN black hole is enhanced in the AdS boundary while it is suppressed in the dS boundary. In addition, the dragging of particles in the KN black hole diminishes the emission of charges in both AdS and dS spaces. The AdS geometry of near-horizon gives the Breitenloher–Freedman (BF) bound, within which the stability of dyonic KN black holes is guaranteed against both the emission of charges and Hawking radiation.

Sang Kim

Dyon production from near-extremal Kerr–Newman–(anti-)de Sitter black holes

We discuss the quantum improvement of black hole solutions in the context of asymptotic safety. The Newton coupling in this formulation depends on an energy scale, which must be identified with some length scale in order to study physical consequences to black holes. However, no physical principle has so far been known for the identification. Here we propose that the consistency of the first law of thermodynamics is the principle that should determine physically sensible scale identification, at least close to the horizon. We show that this leads to a natural solution that the Newton coupling should be a function of the horizon area and find a universal formula for the quantum entropy, which agrees with the standard Bekenstein-Hawking entropy for constant Newton coupling, for Kerr black holes and other higher-dimensional black holes. This suggests that the Newton coupling is a function of the area near the horizon, and also away to infinity, where the quantum effects may not be so important.

Yi Chen

Akihiro Ishibashi

Nobuyoshi Ohta

Daiki Yamaguchi

Running Newton coupling, scale identification, and black hole thermodynamics

The <math><mrow><mi>AdS</mi><mo>/</mo><mi>CFT</mi></mrow></math> correspondence provides a unique way to study the vortex matter phases in superconductors. We solve the dynamical evolution of a superconductor in <math><mrow><mn>2</mn><mo>+</mo><mn>1</mn></mrow></math> dimensions at a finite temperature subjected to a magnetic field quench in terms of a gravitational “hairy black hole” dual living in an asymptotic <math><mrow><msub><mrow><mi>AdS</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math> space. We exploit this to determine the nature of the equilibrium states realized at long times after the quench of this two dimensional type II superconductor in a perpendicular external uniform magnetic field <math><msub><mi>B</mi><mn>0</mn></msub></math>. This holographic superconductor exhibits the generic lower (<math><msub><mi>B</mi><mrow><mi>c</mi><mn>1</mn></mrow></msub><mo>(</mo><mi>T</mi><mo>)</mo></math>) and upper (<math><msub><mi>B</mi><mrow><mi>c</mi><mn>2</mn></mrow></msub><mo>(</mo><mi>T</mi><mo>)</mo></math>) critical fields. For <math><msub><mi>B</mi><mn>0</mn></msub><mo>&lt;</mo><msub><mi>B</mi><mrow><mi>c</mi><mn>1</mn></mrow></msub><mo>(</mo><mi>T</mi><mo>)</mo></math> the magnetic field is completely expelled revealing the Meissner phase, while the superconductivity is destroyed when <math><msub><mi>B</mi><mn>0</mn></msub><mo>&gt;</mo><msub><mi>B</mi><mrow><mi>c</mi><mn>2</mn></mrow></msub><mo>(</mo><mi>T</mi><mo>)</mo></math>. Abrikosov lattices appear in the range <math><msub><mi>B</mi><mrow><mi>c</mi><mn>1</mn></mrow></msub><mo>(</mo><mi>T</mi><mo>)</mo><mo>&lt;</mo><msub><mi>B</mi><mn>0</mn></msub><mo>&lt;</mo><msub><mi>B</mi><mrow><mi>c</mi><mn>2</mn></mrow></msub><mo>(</mo><mi>T</mi><mo>)</mo></math> that realize various configurations in the form of hexagonal, square and slightly irregular square lattices pending the magnetic field strength and the influence of finite size boundaries. We show this to be consistent with the expectations of Ginzburg-Landau theory where the upper and lower critical fields are associated with the inverse squares of the coherence length and magnetic penetration depth, respectively.

Yu Tian

Netherlands

Jan Zaanen

Holographic Abrikosov lattice: Vortex matter from black hole

We studied the pair production of charged scalar particles of a five-dimensional near extremal Reissner-Nordström-Anti de Sitter (RN-AdS$_{5}$) black hole. The pair production rate and the absorption cross section ratio in full spacetime are obtained and are shown to have a concise relation with their counterparts in the near horizon region. In addition, the holographic descriptions of the pair production, both in the IR CFT in the near horizon region and the UV CFT at the asymptotic spatial boundary of the RN-AdS$_{5}$ black hole, are analyzed in the AdS$_{2}$/CFT$_{1}$ and AdS$_{5}$/CFT$_{4}$ correspondences, respectively. This work gives a complete description of scalar pair production in a near extremal RN-AdS$_{5}$ black hole.

Jun Zhang

Yi-Yu Lin

Hao-Chun Liang

Ke-Jia Chi

Jia-Rui Sun

Pair production in Reissner-Nordström-Anti de Sitter black holes  

We study the Schwinger effect in near-extremal nonrotating black holes in an arbitrary <math><mrow><mi>D</mi><mo>(</mo><mo>≥</mo><mn>4</mn><mo>)</mo></mrow></math>-dimensional asymptotically flat and (A)dS space. Using the near-horizon geometry <math><mrow><msub><mrow><mi>AdS</mi></mrow><mrow><mn>2</mn></mrow></msub><mo>×</mo><msup><mrow><mi>S</mi></mrow><mrow><mi>D</mi><mo>−</mo><mn>2</mn></mrow></msup></mrow></math> of near-extremal black holes with Myers-Perry metric, we find a universal expression of the emission formula for charges that is a multiplication of the Schwinger effects in an <math><msub><mi>AdS</mi><mn>2</mn></msub></math> space and in a two-dimensional Rindler space. The effective temperature of an accelerated charge for the Schwinger effect is determined by the radii of the effective <math><msub><mi>AdS</mi><mn>2</mn></msub></math> space and <math><msup><mi>S</mi><mrow><mi>D</mi><mo>−</mo><mn>2</mn></mrow></msup></math> as well as the mass, charge, angular momentum of the charge, and the radius of the (A)dS space. The Schwinger effect in the asymptotically flat space is more efficient and persistent for a wide range of large black holes for dimensions higher than four. The AdS (dS) boundary enhances (suppresses) the Schwinger effect than the asymptotically flat space. The Schwinger effect persists for a wide range of black holes in the AdS space and has an upper bound in the dS space.

Rong-Gen Cai

Schwinger effect in near-extremal charged black holes in high dimensions

We study the Schwinger effect in near-extremal Reissner-Nordström black holes with electric and/or magnetic charges in (anti-)de Sitter (AdS) space. The formula for the Schwinger effect takes a universal form for near-extremal black holes with the near-horizon geometry of <math><msub><mtext>AdS</mtext><mn>2</mn></msub><mo>×</mo><msup><mi>S</mi><mn>2</mn></msup></math> and with the proper radii for the <math><msub><mtext>AdS</mtext><mn>2</mn></msub></math> space and the two-sphere <math><msup><mi>S</mi><mn>2</mn></msup></math>, regardless of the asymptotically flat or (A)dS space. The asymptotic AdS boundary enhances and the dS boundary suppresses the Schwinger effect, and the small radius of AdS (dS) space reinforces the enhancement and suppression.

Schwinger effect from near-extremal black holes in (A)dS space