Physics and Astronomy · Astronomy and Astrophysics
A theoretical study proposes an experiment in which a mass placed in a quantum superposition could produce an effectively repulsive gravitational effect on another particle. The effect would arise from quantum interference and, if observed, would conflict with general relativity’s description of gravity as always attractive.
A study in The Astrophysical Journal examines how black holes in isolated pairs could acquire spins that are tilted relative to their orbit or point in the opposite direction. The results suggest these features are not necessarily evidence that a pair formed through close encounters in a dense stellar environment.
Researchers developed a neural-network design that enforces exact Lorentz symmetry with minimal additional computational overhead. They applied it to graph-based networks and transformers for particle-physics tasks including amplitude prediction, event generation and identifying jets from top quarks.
Some black holes in the early universe appear unusually massive compared with the galaxies around them. A modelling study suggests that brief, repeated bursts of rapid feeding, triggered by major galaxy mergers, could explain this pattern and the brightness of some active black holes seen by JWST.
