Compact Objects Revealed by SKA and SKA-VLBI

Compact objects represent a crucial interdisciplinary frontier between astronomy and fundamental physics.The SKA/SKA-VLBI, with exceptional sensitivity (at $\mu$Jy levels) and ultrahigh positional precision (at $\mu$as levels), will enable direct, precise measurements of orbital dynamics in compact objects including black holes and neutron stars. This facility is expected to achieve at least three breakthroughs: (1) Developing effective methodologies for detecting and identifying black hole-neutron star binaries to construct observational catalogues, thus advancing investigations into the equation of state of ultra-dense nuclear matter and strong-field relativistic effects; (2) Determining critical parameters such as orbital elements and component masses in compact binaries, yielding insights into stellar structures and evolutionary mechanisms under extreme conditions; (3) Identifying intermediate-mass black holes and measuring their masses to deepen understanding of black hole formation and evolution.