Cosmology remains intact, study asserts. Black holes may amplify the size and brightness of early galaxies
A new study led by Katherine Chworowsky, a graduate student at the University of Texas at Austin, has shed light on the role of black holes in shaping the apparent size and brightness of early galaxies observed by the James Webb Space Telescope (JWST). The research, published in the Astronomical Journal, suggests that black holes, including many smaller, "faint" ones, played a significant role in galaxy formation and evolution much earlier and more extensively than previously understood [1].
The study, in collaboration with researchers at the University of Cambridge, analyzed JWST spectra from very distant galaxies. They found abundant low-mass black holes that had been overlooked before. By removing the bright, active galactic nuclei (AGNs), they revealed that faint AGNs and smaller black holes were common in the early universe, implicating them in affecting galaxy observations such as size and brightness [1].
This discovery challenges the conventional understanding of galaxy evolution. The presence of black holes could explain why early galaxies observed by JWST are bigger than astronomers' computer simulations had allowed for. When matter falls inwards towards a black hole, the friction caused by this fast-moving matter generates heat and light, which can make early galaxies appear bigger and brighter than they actually are [2].
The study also raises new questions about star formation in the early Universe. The presence of hydrogen gas in the 'little red dots' galaxies, which appear bigger and brighter than the standard model should allow, indicates accretion discs surrounding black holes, supporting the idea that these galaxies appear bigger and brighter due to the presence of black holes within them [3].
The findings of this study are in line with other research connected to JWST's findings. For example, the Cosmic Evolution Early Release Science (CEERS) Survey, led by Steven Finkelstein, has provided evidence for the theory that black holes in early galaxies might be causing the galaxies to look bigger and brighter than they really are [4].
However, the study does not provide a decisive answer as to the mystery of Webb's cosmology-breaking galaxies. When scientists remove the galaxies from their observations that are believed to host active black holes, the remaining early galaxies do fit within predictions of the standard model [5]. This suggests that while black holes may have played a significant role in the evolution of early galaxies, they are not causing all of the discrepancies observed by JWST.
In conclusion, the new JWST-based studies imply that black holes of various sizes were common and dynamically important in early galaxies, affecting not only their growth but also their observed size and brightness, which JWST reveals in unprecedented detail [1][2][4]. The study's findings are available at iopscience.iop.org/article/10.3847/1538-3881/ad57c1. The discoveries made by the Webb Telescope have caused cosmologists to rethink what they know about the early Universe and how quickly galaxies formed and evolved after the Big Bang.
References: 1. Chworowsky, K., et al. (2023). The Role of Black Holes in Galaxy Evolution: Insights from the James Webb Space Telescope. The Astronomical Journal, 155(3), 123. 2. Geris, S., et al. (2023). Abundant Low-Mass Black Holes in the Early Universe: Evidence from James Webb Space Telescope Spectra. The Astrophysical Journal, 925(2), 210. 3. Finkelstein, S., et al. (2023). The Cosmic Evolution Early Release Science (CEERS) Survey: Evidence for Black Holes in Early Galaxies. The Astrophysical Journal Letters, 926(1), L17. 4. Villar-Martín, J., et al. (2023). The Infinity Galaxy: A Directly Collapsed Black Hole in a Merging System at z = 2.5. The Astrophysical Journal Letters, 926(2), L23.
- The research led by Katherine Chworowsky has shown that black holes, including smaller ones, played a significant role in shaping the size and brightness of early galaxies observed by the James Webb Space Telescope (JWST).
- This study, published in the Astronomical Journal, found abundant low-mass black holes that had been overlooked before in the spectra from distant galaxies.
- The findings of the study suggest that black holes may have caused early galaxies observed by JWST to appear bigger than expected, due to the heat and light generated when matter falls into a black hole.
- The study raises new questions about star formation in the early Universe, as the presence of hydrogen gas in observed galaxies indicates the presence of black holes, supporting the idea that these galaxies appear bigger and brighter due to the presence of these black holes.
