43 citations · 94 across the 15 of their papers we have counts for
15 papers
Phase Transitions with Lyapunov Exponents under Einstein and String Frames in Dilatonic Reissner--Nordström--AdS Black Holes
Hocheol Lee, Bogeun Gwak
We investigate Lyapunov exponents as dynamical probes of black hole phase transitions in dilatonic Reissner--Nordström--AdS black holes within Einstein--Maxwell--dilaton theory. Th…
Chaotic behaviors of particles around the black hole with an anisotropic matter immersed in a magnetic field
Khusan Alibekov, Hocheol Lee, Yovqochev Pahlavon +6
We present an exact solution to the Einstein-Maxwell equations that describes a static black hole coexisting with anisotropic matter immersed in an external magnetic field, obtaine…
Phase transition for a black hole with matter fields and the relation with the Lyapunov exponent
Pakhlavon Yovkochev, Bobomurat J. Ahmedov, Bum-Hoon Lee +2
We construct static black hole solutions coexisting with anisotropic matter in asymptotically (anti-)de Sitter spacetime and investigate how the matter field modifies their thermod…
Gauss-Bonnet corrected string/black hole transition in large dimensions
Bum-Hoon Lee, Hocheol Lee, Somyadip Thakur
We develop a unified analytic treatment of the Horowitz--Polchinski string/black hole correspondence that systematically incorporates higher-derivative corrections to gravity. Work…
Unbounded Radius of Innermost Stable Circular Orbit in Higher-Dimensional Black Holes
Hocheol Lee, Bogeun Gwak
The innermost stable circular orbit (ISCO) offers a fundamental test of spacetime structure. However, its behavior in higher-dimensional black holes influenced by anisotropic energ…
Frame Dependence of Bound on Lyapunov Exponent in Dilatonic Reissner-Nordström-AdS and Kerr-Sen-AdS Black Holes
Hocheol Lee, Bogeun Gwak
We investigate the frame dependence of the Lyapunov exponent bound for charged particles in dilatonic Reissner-Nordström-AdS and Kerr-Sen-AdS black hole backgrounds, derived from E…
Bound on Lyapunov exponent for a charged particle in Kerr-Sen-AdS Black Hole
Hocheol Lee, Bogeun Gwak
We investigate the upper bound of the Lyapunov exponent for a charged particle in the Gibbons--Maeda--Garfinkle--Horowitz--Strominger (GMGHS)--AdS and Kerr--Sen--AdS black hole bac…
Traversable wormhole for string, but not for particle
Hun Jang, Minkyoo Kim, Hocheol Lee +1
We propose a Lorentzian wormhole geometry characterized by a closed string massless sector with nontrivial -flux and a scalar dilaton. In the string frame, the dilaton exhibits…
Gauss-Bonnet Cosmology: large-temperature behaviour and bounds from Gravitational Waves
Anirban Biswas, Arpan Kar, Bum-Hoon Lee +5
We provide a transparent discussion of the high temperature asymptotic behaviour of Cosmology in a dilaton-Einstein-Gauss-Bonnet (dEGB) scenario of modified gravity with vanishing…
Induced Cosmological Anisotropies and CMB Anomalies by a non-Abelian Gauge-Gravity Interaction
Bum-Hoon Lee, Hocheol Lee, Wonwoo Lee +2
We present a non-abelian cousin of the model presented in \cite{Lee:2022rtz} which induces cosmological anisotropies on top of standard FLRW geometry. This is in some sense doing a…
Late-time Cosmology without Dark Sector but with Closed String Massless Sector
Hocheol Lee, Jeong-Hyuck Park, Liliana Velasco-Sevilla +1
We explore the possibility of solving the dark energy and the coincidence problems by postulating the massless sector of closed strings. This sector constitutes the gravitational m…
WIMPs in Dilatonic Einstein Gauss-Bonnet Cosmology
Anirban Biswas, Arpan Kar, Bum-Hoon Lee +5
We use the Weakly Interacting Massive Particle (WIMP) thermal decoupling scenario to probe Cosmologies in dilatonic Einstein Gauss-Bonnet (dEGB) gravity, where the Gauss-Bonnet ter…
Homoclinic orbit and the violation of the chaos bound around a black hole with anisotropic matter fields
Soyeon Jeong, Bum-Hoon Lee, Hocheol Lee +1
We study the homoclinic orbit and the violation of chaos bound, which are obtained by particle motions around a black hole that coexist with anisotropic matter fields. The homoclin…
Induced cosmological anisotropy by a gauge-gravity interaction
Bum-Hoon Lee, Hochoel Lee, Wonwoo Lee +2
We present a simple model which generates cosmological anisotropies on top of standard FLRW geometry. This is in some sense reminiscent of the mean field approximation, where the m…
Violation of bound on chaos for charged probe in Kerr-Newman-AdS black hole
Bogeun Gwak, Naoto Kan, Bum-Hoon Lee +1
We investigate the conjectured bound on the Lyapunov exponent for a charged particle with angular motion in the Kerr-Newman-AdS black hole. The Lyapunov exponent is calculated base…