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.