Quasars, supermassive black holes, and galaxy formation
How do the supermassive black holes that power quasars and sit at galaxy centers form and grow, and how do galaxies themselves assemble over cosmic time?
History and references
Partly settled. Some of it is understood, some is still argued about.
The presence of a roughly 4-million-solar-mass supermassive black hole at the center of our own galaxy was confirmed by tracking stellar orbits (work honored by the 2020 Nobel Prize to Genzel and Ghez) and was directly imaged by the Event Horizon Telescope in 2022. Yet the overall theory of galaxy formation remains incomplete: JWST observations from 2022 onward have found surprisingly massive, mature-looking galaxies only a few hundred million years after the Big Bang (Labbe et al. 2023), in tension with standard LCDM galaxy-formation timelines — an active debate as of 2026.
Every large galaxy, including our own, appears to have grown around a black hole millions of times the sun's mass at its center, and nobody fully understands which came first.
References
- What problems of physics and astrophysics seem now to be especially important and interesting (thirty years later, already on the verge of the XXI century)?, V L Ginzburg, Physics-Uspekhi 42 (4) 353-373, 1999
- The Nobel Prize in Physics 2020 (for the discovery of a supermassive compact object at the centre of our galaxy), NobelPrize.org press release, 2020
- A population of red candidate massive galaxies ~600 Myr after the Big Bang, I. Labbe et al., Nature 616, 266, 2023
Solutions 0
Sign in or create an account to publish a solution