Information
Membership Number: CFCA3119
Membership Type: Corresponding Fellow
Division: Natural Sciences
Corresponding Email: ahmadjon@astrin.uz; abahmadjon@yahoo.com, ahmadjon@fudan.edu.cn
Homepage(s): https://orcid.org/0000-0002-6686-3787
Present and Previous Positions
Leading Researcher, Ulugh Beg Astronomical Institute, Astronomicheskaya 33, Tashkent 100052, Uzbekistan
Fields of Scholarship and Research Interests
Theoretical research in the field of electrodynamics, relativistic astrophysics and general relativity
Professor Ahmadjon Abdujabbarov’s research is devoted to exploring fundamental problems in General Relativity, Relativistic Astrophysics, and Modified Theories of Gravity, with particular emphasis on the dynamics of compact objects such as black holes, wormholes, and neutron stars. A central theme of his work is the study of particle motion, gravitational lensing, and black hole shadows as powerful astrophysical probes of gravity in both classical and extended theoretical frameworks. By combining rigorous theoretical modeling with astrophysical applications, his research bridges the gap between observational data and the foundations of gravitational physics.
A significant portion of his contributions addresses the dynamics of particles and fields in curved spacetimes. He has investigated the behavior of charged, spinning, and magnetized particles around a wide range of black hole solutions, including those in Einstein–Maxwell-scalar, Einstein–Gauss–Bonnet, Horndeski, and Lorentz gauge theories. These studies shed light on key astrophysical processes such as accretion, quasi-periodic oscillations (QPOs), jet formation, and high-energy collisions, including energy extraction mechanisms like the Penrose process.
Another major line of his research concerns black hole optics. Professor Abdujabbarov has extensively analyzed the formation and properties of black hole shadows and gravitational lensing, both in vacuum and in the presence of astrophysical media such as plasma and dark matter. His work not only constrains deviations from the Kerr geometry but also provides essential tools for interpreting observations from instruments such as the Event Horizon Telescope. He has also extended gravitational optics to neutrinos and electromagnetic fields, broadening the scope of strong-gravity phenomenology.
In collaboration with colleagues, Professor Abdujabbarov has contributed substantially to the study of modified gravity and quantum gravity phenomenology. His research tests alternative theories—including Einstein-Æther, Rastall gravity, f(R) models, Horndeski theory, conformal Weyl gravity, and teleparallel gravity—through astrophysical signatures, thereby assessing their viability against General Relativity. His investigations of wormholes, regular black holes, and exotic spacetimes have revealed rich phenomenology in shadow images, QPO spectra, and lensing patterns, offering potential observational discriminators for beyond-GR scenarios.
He has also explored the interplay between electromagnetic fields and compact objects, including magnetized black holes and neutron stars. These studies illuminate plasma interactions, synchrotron radiation, and magnetic Penrose processes, which are crucial for understanding astrophysical jets and accretion disks. His work demonstrates how electromagnetic signatures can uncover hidden features of exotic spacetimes, enriching the multi-messenger approach to strong gravity.
Among his methodological innovations, Professor Abdujabbarov and collaborators have developed a coordinate-independent formalism for analyzing black hole shadows using Legendre expansions. This approach allows shadows to be represented as general polar curves without assumptions of symmetry, offering a universal framework for quantifying shadow distortions and comparing observational data. His studies on plasma effects around Kerr black holes further demonstrate how environmental factors—such as plasma density, spin, and inclination—affect shadow images, providing direct input for the interpretation of Event Horizon Telescope data.
Beyond these, his research covers a broad range of astrophysical and theoretical phenomena: ultra-high-energy collisions near near-extremal naked singularities in Hořava gravity, rotating regular black hole solutions, polarization effects in non-Kerr spacetimes, Penrose processes in various gravity models, and thermodynamics of charged rotating black holes in dark-matter environments. His studies of test particle dynamics and QPOs across different gravity theories provide both theoretical insights and observational constraints, strengthening the dialogue between gravitational theory and astrophysical data.
With over a hundred publications in leading international journals, Professor Abdujabbarov has established a coherent and influential research program that links theoretical modeling of compact objects, tests of fundamental physics, and astrophysical applications. His work continues to deepen our understanding of strong-field gravity while providing testable predictions for current and upcoming astronomical observations.
Honors, Awards and Other Membership
Governmental Medal “Shukhrat”, Republic of Uzbekistan (2021)
Scopus–Elsevier Prize: Best Researcher in Engineering (2019)
Best Young Researcher Prize, National University of Uzbekistan (2018)
Selected as TWAS Young Affiliate (five-year term) (2018)
Web of Science–Clarivate Analytics Prize: Best Young Researcher (2017)
TWAS Prize for Young Scientist (2014)
Best Scientific Publication Award, Uzbek Academy of Sciences (2013)
Best Poster Prize, Institute of Physics (IoP), Plasma Physics and Controlled Fusion (October 12, 2011)
Second Place, Competition at the 3rd National Conference of Young Scientists of Uzbekistan: “Nuclear Physics and Nuclear Technologies” (December 1–2, 2010)
National Stipendium “Kamolot” for Young Scientists (2010)
State Scholarship named after the President of the Republic of Uzbekistan in Natural Sciences (2006–2007)
SUMITOMO Corporation Scholarships (Japan), three years (2003, 2004, 2005)
Selected Publications
https://scholar.google.de/citations?user=YjhKvPoAAAAJ&hl=en
Other Information
Acceptance Letter_CORE.pdf
