A5001054311- Pulsars and Gravitational Waves Research
- Cosmology and Gravitation Theories
- Geophysics and Gravity Measurements
- Astrophysical Phenomena and Observations
- Black Holes and Theoretical Physics
- Solar and Space Plasma Dynamics
- Relativity and Gravitational Theory
- Advanced Frequency and Time Standards
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Noncommutative and Quantum Gravity Theories
- Adaptive optics and wavefront sensing
- Advanced Optical Imaging Technologies
- Photorefractive and Nonlinear Optics
- Photonic and Optical Devices
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Dark Matter and Cosmic Phenomena
- Superconducting and THz Device Technology
- Liquid Crystal Research Advancements
- Quantum chaos and dynamical systems
- Terahertz technology and applications
- MicroRNA in disease regulation
- Astronomy and Astrophysical Research
- Galaxies: Formation, Evolution, Phenomena
Purple Mountain Observatory
2022-2024
Chinese Academy of Sciences
2009-2024
University of Chinese Academy of Sciences
2022-2024
Aerospace Information Research Institute
2024
South China Sea Institute Of Oceanology
2022-2023
Institute of Oceanology
2022-2023
Nanjing University
2013-2022
Ji Hua Laboratory
2022
Institute of Modern Physics
2014-2022
Peking University
2017-2022
The effects of the f (T) gravity have previously been investigated and constrained by using perihelion advances. As an extension previous work as attempt to find more stringent constraints on its parameters, we investigate here astronomical observations experiments conducted in Solar system. expression for contains a quadratic correction α*T2 (where α is model parameter) cosmological constant Λ. Using spherical solution describing Sun's gravitational field, resulting secular evolution...
A charged black hole was predicted by the Einstein--Horndeski--Maxwell theory. In order to provide its observational signatures, we investigate weak and strong deflection gravitational lensings. We find lensing observables, including positions, magnifications differential time delay of lensed images. also obtain apparent radius photon sphere as well angular separation, brightness difference between relativistic Taking supermassive in Galactic Center lens, evaluate these observables compare...
Abstract Weak and strong deflection gravitational lensing by a renormalization group improved Schwarzschild black hole is investigated its observables are found. By taking the supermassive holes Sgr A* M87* respectively in Galactic Center at center of M87 as lenses, we estimate these analyse possibility detecting this quantum improvement. It not feasible to distinguish such most near future except for apparent size shadow. We also note that directly using measured shadow constrain effect...
In the strong deflection gravitational lensing, given fact that a black-bounce, traversable wormhole is indistinguishable from Schwarzschild black hole and loosely tested by Event Horizon Telescope, we intensively study its signatures of weak lensing in light tremendous progress made new generation near-infrared interferometer GRAVITY. After obtaining observables, which are positions, magnitudes brightness, centroid, differential time delay between lensed images, investigate three...
Abstract We investigate the weak and strong deflection gravitational lensing by a quantum deformed Schwarzschild black hole find their observables. These observables are evaluated detectability of deformation is assessed, after assuming supermassive holes Sgr A* M87* respectively in Galactic Center at center M87 as lenses. also intensively compare these findings with those renormalization group improved an asymptotically safe hole. that, among holes, it most likely to test via its foreseen future.
We investigate the weak and strong deflection gravitational lensing by hairy black holes in Einstein-scalar-Gauss-Bonnet (EsGB) gravity with five types of coupling functions (quadratic, cubic, quartic, inverse-polynomial, logarithmic), which can evade no-hair theorem. The observables are found possibility detecting effects scalar hair is analyzed. find that all shadows cast these consistent measurement Event Horizon Telescope, while other beyond present capacity. Therefore, it currently...
Abstract We investigate the weak and strong deflection gravitational lensing by a black-bounce-Reissner–Nordström spacetime obtain their observables. Assuming supermassive black holes in Galactic Center at center of M87, Sgr A* M87* respectively, as lenses, we evaluate these observables assess detectability. also intensively compare signatures with those various tidal or charged spacetimes. find that it might be possible to distinguish spacetimes measuring fluxes difference lensed images its...
Beyond the Einstein–Maxwell model, electromagnetic field might couple with gravitational through Weyl tensor. In order to provide one of missing puzzles whole physical picture, we investigate weak deflection lensing for photons coupled tensor in a Schwarzschild black hole under unified framework that is valid its two possible polarizations. We obtain coordinate-independent expressions all observables geometric optics up second terms $$\varepsilon $$ which ratio angular radius Einstein lens....
We investigate weak and strong deflection gravitational lensings of the regular black hole predicted by a non-minimal Einstein–Yang–Mills theory. find that its lensing is same as Reissner–Nordström hole's. Observables in lensing, including apparent radius photon sphere (shadow) well angular separation, brightness difference time delay between relativistic images, are obtained analyzed for supermassive holes Sgr A* M87* Galactic Center at center M87. only radii spheres within ability current...
Abstract We investigate precessing and periodic geodesic motions of timelike particles around a black-bounce/traversable wormhole. After obtaining its semi-classic relativistic periastron advance, we find preliminary bound on the scale length such spactime based detected precession star S2 Galactic Center. also study orbits it that variation can change taxonomy cause transition from orbit to quasi-periodic one vice versa.
This paper is mainly devoted to applying the invariant, fast, Lyapunov indicator clarify some doubt regarding apparently conflicting results of chaos in spinning compact binaries at second-order post-Newtonian approximation general relativity from previous literatures. It shown with a number examples that no single physical parameter or initial condition can be described as responsible for causing chaos, but complicated combination all parameters and conditions responsible. In other words,...
The phase space of a Hamiltonian system is symplectic. However, the post-Newtonian formulation spinning compact binaries in existing publications does not have this property, when position, momentum and spin variables $[X, P, S_1, S_2]$ compose its space. This may give convenient application perturbation theory to derivation formulation, but also makes classic theories symplectic be serious obstacle application, especially diagnosing integrability nonintegrability from dynamical perspective....
Ground-based and space-borne observatories studying exoplanetary transits now in the future will considerably increase number of known exoplanets precision measured times transit minima. Variations can not only be used to infer presence additional planets, but might also provide opportunities for testing new physics places beyond Solar system. In this work, we take deviation from inverse-square law gravity as an example, focus on fifth-force-like Yukawa-type correction Newtonian...
We study strong deflection gravitational lensing by a Lee–Wick black hole, which is non-singular hole generated high derivative modification of Einstein–Hilbert action. The expected to produce set relativistic images very closed the event horizon hole. estimate its observables for supermassive in our Galactic center. It found that can be distinguished from Schwarzschild via such effects when UV scale not large, but requiring resolution much higher than current capability.
Full general relativity requires that chaos indicators should be invariant in various spacetime coordinate systems for a given relativistic dynamical problem. On the basis of this point, we calculate Lyapunov exponents (LEs) one spinning compact binaries conservative second post-Newtonian (2PN) Lagrangian formulation without dissipative effects gravitational radiation, using two-nearby-orbits method with projection operations and time as an independent variable. It is found actual source...
A gravity theory called scalar-tensor-vector (STVG) has been recently developed and succeeded in solar system, astrophysical, cosmological scales without dark matter [1]. However, two assumptions have used: (i) $B(r)={A}^{\ensuremath{-}1}(r)$, where $B(r)$ $A(r)$ are ${g}_{00}$ ${g}_{rr}$ the Schwarzschild coordinates (static spherically symmetric); (ii) scalar field $G=\mathrm{Const}.$ system. These actually imply that standard parametrized post-Newtonian parameter $\ensuremath{\gamma}=1$....
Hometown ties help Chinese scientists get ahead
A modified Hayward black hole is a nonsingular hole. It proposed that it would form when the pressure generated by quantum gravity can stop matter's collapse as matter reaches Planck density. Strong deflection gravitational lensing occurring nearby its event horizon might provide some clues of these effects in central core. We investigate observables strong lensing, including angular separations, brightness differences and time delays between relativistic images, we estimate their values for...
Abstract We study strong deflection gravitational lensing by a Lee-Wick ultracompact object. Its unique feature is series of relativistic images inside its photon sphere, which are absent in the case black hole. obtain observables and estimate them for supermassive holes Sgr A* M87* respectively Galactic center M87. find that innermost image very promising signature according to angular separation from sphere considerable brightness. A preliminary bound on UV scale such an object estimated...