Results 51 to 60 of about 2,382,221 (211)

First Detection of an Overmassive Black Hole Galaxy UHZ1: Evidence for Heavy Black Hole Seed Formation from Direct Collapse

The Astrophysical Journal Letters, 2023
The recent Chandra-JWST discovery of a quasar in the z ≈ 10.1 galaxy UHZ1 reveals that accreting supermassive black holes were already in place 470 million years after the Big Bang. The Chandra X-ray source detected in UHZ1 is a Compton-thick quasar with
Priyamvada Natarajan, Fabio Pacucci, Angelo Ricarte, Ákos Bogdán, Andy D. Goulding, Nico Cappelluti   +5 more
doaj   +1 more source

Primordial black holes as dark matter candidates

SciPost Physics Lecture Notes, 2022
We review the formation and evaporation of primordial black holes (PBHs) and their possible contribution to dark matter. Various constraints suggest they could only provide most of it in the mass windows $10^{17}$ - $10^{23}\,$g or $10$ - $10^{2}\,M_ ...
Bernard Carr, Florian Kuhnel
doaj   +1 more source

Boundary‐Only Weak Deflection by Regular Black Holes, Black‐Bounces, Wormholes, and Static Quadrupolar Spacetimes

Fortschritte der Physik, Volume 74, Issue 8, August 2026.
ABSTRACT We apply the boundary‐only isothermal formulation of finite‐distance weak gravitational deflection to regular black holes, black‐bounces, traversable wormholes, non‐asymptotically flat backgrounds, and static quadrupolar spacetimes. The methodological advance is not a new value for a known bending angle.
Reggie C. Pantig, Ali Övgün
wiley   +1 more source

Evolution of Supermassive Black Holes [PDF]

, 2007
Supermassive black holes (SMBHs) are nowadays believed to reside in most local galaxies, and the available data show an empirical correlation between bulge luminosity - or stellar velocity dispersion - and black hole mass, suggesting a single mechanism for assembling black holes and forming spheroids in galaxy halos. The evidence is therefore in favour
openaire   +2 more sources

The GLEAMing of the first supermassive black holes

Publications of the Astronomical Society of Australia, 2020
AbstractWe present the results of a new selection technique to identify powerful ($L_{\rm 500\,MHz} \gt 10^{27}\,\text{WHz}^{-1}$) radio galaxies towards the end of the Epoch of Reionisation. Our method is based on the selection of bright radio sources showing radio spectral curvature at the lowest frequency (${\sim}100\,\text{MHz}$) combined with the ...
Guillaume Drouart, Nick Seymour, Tim J. Galvin, Jose Afonso, Joseph R. Callingham, Carlos De Breuck, Melanie Johnston-Hollitt, Anna D. Kapińska, Matthew D. Lehnert, Joël Vernet   +9 more
openaire   +5 more sources

Supermassive black holes in the early Universe [PDF]

Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2015
The recent discovery of the ultraluminous quasar SDSS J010013.02+280225.8 at redshift 6.3 has exacerbated the time compression problem implied by the appearance of supermassive black holes only approximately 900 Myr after the big bang, and only approximately 500 Myr beyond the formation of Pop II and III stars. Aside from heralding
F. Melia, T. M. McClintock
openaire   +2 more sources

Fundamental physics opportunities with the next-generation Event Horizon Telescope

Living Reviews in Relativity
The Event Horizon Telescope (EHT) Collaboration recently published the first images of the supermassive black holes in the cores of the Messier 87 and Milky Way galaxies.
Dimitry Ayzenberg, Lindy Blackburn, Richard Brito, Silke Britzen, Avery E. Broderick, Raúl Carballo-Rubio, Vitor Cardoso, Andrew Chael, Koushik Chatterjee, Yifan Chen, Pedro V. P. Cunha, Hooman Davoudiasl, Peter B. Denton, Sheperd S. Doeleman, Astrid Eichhorn, Marshall Eubanks, Yun Fang, Arianna Foschi, Christian M. Fromm, Peter Galison, Sushant G. Ghosh, Roman Gold, Leonid I. Gurvits, Shahar Hadar, Aaron Held, Janice Houston, Yichao Hu, Michael D. Johnson, Prashant Kocherlakota, Priyamvada Natarajan, Héctor Olivares, Daniel Palumbo, Dominic W. Pesce, Surjeet Rajendran, Rittick Roy, Saurabh, Lijing Shao, Shammi Tahura, Aditya Tamar, Paul Tiede, Frédéric H. Vincent, Luca Visinelli, Zhiren Wang, Maciek Wielgus, Xiao Xue, Kadri Yakut, Huan Yang, Ziri Younsi   +47 more
doaj   +1 more source

Slowly Rotating Traversable Wormholes Supported by Radially Varying String‐Fluid Matter: From Regular Geometries to Photon Trajectories

Annalen der Physik, Volume 538, Issue 6, June 2026.
This study examines slowly rotating traversable wormholes supported by string fluids whose properties change with radius. The matter smoothly shifts from a de Sitter‐like core to a string‐dominated exterior, producing a regular, horizon‐free spacetime.
A. Errehymy, B. Turimov, Meraj Ali Khan, S. Usanov, Z. Yasakov, Z. Avezmuratova   +5 more
wiley   +1 more source

Supermassive black holes in galactic bulges [PDF]

Monthly Notices of the Royal Astronomical Society: Letters, 2008
Abstract Growing evidence indicate supermassive black holes (SMBHs) in a mass range of MBH∼ 106–1010 M⊙ lurking in central stellar bulges of galaxies. Extensive observations reveal fairly tight power laws of MBH versus the mean stellar velocity dispersion σ of the host stellar bulge.
Lou, Yu-Qing, Jiang, Yan-Fei
openaire   +2 more sources

Geodesic Geometry of Black Holes [PDF]

, 2006
The study of geodesics is of intrinsic significance in the study of the geometry of space-time. In this thesis null, space-like and time-like geodesics are studied in the case of the space-times of Schwarzschild, Reissner-Nordstrouml;m and Kerr black ...
Slezakova, Gabriela
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