Results 51 to 60 of about 6,310 (180)
Primordial black holes as supermassive black hole seeds
Journal of Cosmology and Astroparticle PhysicsAbstract The presence of supermassive black holes (SMBHs, M • ∼ 106-10 M ⊙) in the first cosmic Gyr (z ≳ 6) challenges current models of BH formation and evolution. We propose a novel mechanism for the formation of early SMBH seeds based on primordial black holes (PBHs).
F. Ziparo, S. Gallerani, A. Ferrara
openaire +2 more sources
Asymptotically‐Flat Black Hole Solutions in Symmergent Gravity
Fortschritte der Physik, Volume 72, Issue 4, April 2024.Abstract Symmergent gravity is an emergent gravity model with an R+R2$R+R^2$ curvature sector and an extended particle sector having new particles beyond the known ones. With constant scalar curvature, asymptotically flat black hole solutions are known to have no sensitivity to the quadratic curvature term (coefficient of R2$R^2$). With variable scalar
Beyhan Puliçe +3 more
wiley +1 more source
Differential rotation in compact objects with hyperons and delta isobars
Astronomische Nachrichten, Volume 345, Issue 2-3, February-March 2024.Abstract Neutron stars may experience differential rotation on short, dynamical timescales following extreme astrophysical events like binary neutron star mergers. In this work, the masses and radii of differentially rotating neutron star models are computed.
Delaney Farrell +3 more
wiley +1 more source
On the location of the supermassive black hole in CTA 102 [PDF]
Astronomy & Astrophysics, 2015 Relativistic jets in active galactic nuclei represent one of the most powerful phenomena in the Universe. They form in the surroundings of the supermassive black holes as a by-product of accretion onto the central black hole in active galaxies. The flow in the jets propagates at velocities close to the speed of light.
Fromm, Christian M. +4 more
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A NORMAL SUPERMASSIVE BLACK HOLE IN NGC 1277 [PDF]
The Astrophysical Journal, 2016 ABSTRACT The identification of galaxies with “overly massive” black holes requires two measurements: a black hole mass (M bh) and a host spheroid mass ( ). Here we provide our measurements for NGC 1277.
Alister W. Graham +7 more
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Constraints on alternatives to supermassive black holes [PDF]
Monthly Notices of the Royal Astronomical Society: Letters, 2006 Abstract Observations of the centres of galaxies continue to evolve, and it is useful to take a fresh look at the constraints that exist on alternatives to supermassive black holes at their centres. We discuss constraints complementary to those of Maoz and demonstrate that an extremely wide range of other possibilities can be excluded ...
openaire +2 more sources
Supermassive black holes and their feedback effects in galaxy formation [PDF]
, 2018 Supermassive black holes play a key role in modern galaxy formation research. They are conjectured to be present in almost all massive galaxies, and through the release of enormous amounts of energy triggered by gas accretion, they are able to ...
Weinberger, Rainer
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Geodesic Geometry of Black Holes
, 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
core
Joint Formation of Supermassive Black Holes and Galaxies
, 2018 The tight correlation between black hole mass and velocity dispersion of galactic bulges is strong evidence that the formation of galaxies and supermassive black holes are closely linked. I review the modeling of the joint formation of galaxies and their
core +1 more source
Gravitational Waves from Supermassive Black Holes
, 2016 In this talk, I will present the first direct detections of gravitational waves from binary stellar-mass black hole mergers during the first observing run of the two detectors of the Advanced Laser Interferometer Gravitational-wave Observatory, which ...
di Girolamo, Tristano +1 more
core +2 more sources