Dear Colleagues,

A recent observation of M87* by EHT shows that this central BH is surrounded by plasma and magnetic fields. Moreover, there are many other previous observations of black holes with high-energy activities such as jet formations, accretion disks, quasiperiodic oscillations, etc. All of these black hole activities demonstrate the relevance of different particles, fluids, or plasma processes near black holes. Since the exact nature of the physical nature of M87* is not precisely understood in more detail, the impetus of this Special Issue is to compare and test various phenomenological models of the galactic center and astrophysical processes, such as magnetic field generation and accretion rate, with the latest astronomical observations.

This Special Issue will focus on both observational and theoretical studies of astrophysical processes near black holes. The topics of interest for this Special Issue include (but are not limited to):

Classical and modern gravitational theories;

Phenomenological models of spherical and the axis-symmetric accretion on compact objects;

Magnetic field generation and evolution and MHD processes in the black hole vicinity;

Charged particle dynamics and their orbits near black holes;

In addition, new and future data should be explored, such as X-ray, gamma-ray, and gravitational waves.

The existing articles on the topics of our interest in general relativity and astrophysics ignore aspects of astronomical data and observations. We encourage authors to submit articles supplemented with substantial evidence of astronomical data that incorporate the theory of black hole physics.

Dr. Qiang Wu
Prof. Dr. Mubasher Jamil
Dr. Tao Zhu
Guest Editors

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• multi-messenger astronomy
• multi-wavelength observations
• high-energy astrophysics
• modified theory of gravity
• black holes
• accretion
• plasma
• data analysis techniques
• deep learning