Results 61 to 70 of about 8,827 (222)
Eötvös experiments with supermassive black holes [PDF]
By examining the locations of central black holes in two elliptical galaxies, M\,32 and M\,87, we derive constraints on the violation of the strong equivalence principle for purely gravitational objects, i.e. black holes, of less than about two-thirds, $η_N<0.68$ from the gravitational interaction of M\,87 with its neighbours in the Virgo cluster ...
Asvathaman, Asha +2 more
openaire +1 more source
Axion Black Hole Solution in Non‐Metricity Gravity
Abstract A static, spherically symmetric black hole solution in symmetric teleparallel (non‐metricity) gravity sourced by an axion field is constructed. Starting from the modified field equations, exact configurations are obtained characterized by the mass M$M$ and an axion–geometry coupling β$\beta$, with temporal metric function A(r)=1−2Mr+βr$A(r)=1-\
A. Eid, G.G.L. Nashed
wiley +1 more source
Star cluster black hole, 2013 [PDF]
Image of star cluster black hole. Scientists had believed that supermassive black holes, located at the centres of galaxies, increased their mass in step with the growth of their host galaxy.
Alister W. Graham, Gabriel Perez Diaz
core
We examine the weak cosmic censorship conjecture (WCCC) violation by throwing a charged and rotating test particle into a Kerr–Newman–modified gravity black hole (KN–MOG BH). The result depends on several factors, such as the relative sign of the particle’s charge and its direction of rotation with respect to black hole (BH).
Waqar Ahmad +2 more
wiley +1 more source
The Black Hole Spin Controversy [PDF]
Astrophysical black holes are the simplest possible objects. They are completely described by only two parameters in general relativity, their mass and the specific angular momentum, spin.
KOLEHMAINEN, MARI,JOHANNA +1 more
core
Braneworld black holes and black strings [PDF]
This thesis involves the study of strong and weak gravity phenomenology within the braneworld paradigm. We begin with a general overview of the hypothesised concept of extra spatial dimensions and explain why they are so interesting.
Mistry, Bina
core
From Nuclear Star Clusters to Little Red Dots: Black Hole Growth, Mergers, and Tidal Disruptions
Little Red Dots, discovered by the James Webb Space Telescope, are hypothesized to be active galactic nuclei containing a supermassive black hole, possibly surrounded by a dense stellar cluster, large amounts of gas, and likely by a population of stellar-
Konstantinos Kritos, Joseph Silk
doaj +1 more source
The GLEAMing of the first supermassive black holes
AbstractWe present the results of a new selection technique to identify powerful ($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 +9 more
openaire +5 more sources
Supermassive black holes in the early Universe [PDF]
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
Deep Space Network Radio Science and Ground‐Based Planetary Radar in the Next Decade
Abstract The Deep Space Network (DSN) has been a core operational element of NASA's crewed and robotic exploration of the Solar System since the early 1960s. The primary role of the DSN has been to acquire telemetry and navigation data, but over the years, its radiometric and radar capabilities have expanded to form a system for obtaining unique ...
R. S. Park +13 more
wiley +1 more source

