Related papers: Black Holes at Work
We review some recent results obtained for black holes using effective field theory methods applied to quantum gravity, in particular the unique effective action. Black holes are complex thermodynamical objects that not only have a…
Models of superdense star clusters at the center of galaxies are investigated to see whether such objects can be stable and long-lived based on evaporation and collision time-scales and stability criteria. We find that physically reasonable…
Two interesting hypotheses about black holes have been proposed. The older one states that microscopic black holes can be accountable for the observed dark matter density. The newer one states that black holes are coupled to the expansion…
Active galaxies contain a supermassive black hole at their center, which grows by accreting matter from the surrounding galaxy. The accretion process in the central ~10 parsecs has not been directly resolved in previous observations, due to…
Stellar-mass black holes (BHs), with masses comparable to stars, are a major constituent of our Milky Way galaxy. This chapter describes the landscape of challenging, and long-sought efforts to identify these objects in the Galaxy. The…
Black holes are extremely dense and compact objects from which light cannot escape. There is an overall consensus that black holes exist and many astronomical objects are identified with black holes. White holes were understood as the exact…
Massive black holes (MBHs) are nowadays recognized as integral parts of galaxy evolution. Both the approximate proportionality between MBH and galaxy mass, and the expected importance of feedback from active MBHs in regulating star…
Massive black holes are fundamental constituents of our cosmos, from the Big Bang to today. Understanding their formation from cosmic dawn, their growth, and the emergence of the first, rare quasars in the early Universe remains one of our…
A combination of ground-based and spacecraft observations has uncovered two black holes of 10 billion solar masses in the nearby Universe. The finding sheds light on how these cosmic monsters co-evolve with galaxies.
This review discusses the current status of supermassive black hole research, as seen from a purely observational standpoint. Since the early '90s, rapid technological advances, most notably the launch of the Hubble Space Telescope, the…
The existence of supermassive collapsed objects in the cores of most galaxies poses still-unanswered questions. First, how did they form, and how does their mass depend on the properties of the host galaxy? Second, can observations probe…
Black holes are the elementary particles of gravity, the final state of sufficiently massive stars and of energetic collisions. With a forty-year long history, black hole physics is a fully-blossomed field which promises to embrace several…
Evidence shows that massive black holes reside in most local galaxies. Studies have also established a number of relations between the MBH mass and properties of the host galaxy such as bulge mass and velocity dispersion. These results…
The possible existence of black holes has fascinated scientists at least since Michell and Laplace's proposal that a gravitating object could exist from which light could not escape. In the 20th century, in light of the general theory of…
Massive black holes often exist within dwarf galaxies, and both simulations and observations have shown that a substantial fraction of these may be off-center with respect to their hosts. We trace the evolution of off-center massive black…
Perturbations around black holes have been an intriguing topic in the last few decades. They are particularly important today, since they relate to the gravitational wave observations which may provide the unique fingerprint of black holes'…
Massive black holes are thought to reside at the centres of many galaxies, where they power quasars and active galactic nuclei. But most galaxies are quiescent, indicating that any central massive black hole present will be starved of fuel…
Supermassive binary black holes and their influence on the structure and evolution of galaxies is reviewed.
The most massive black holes, lurking at the centers of large galaxies, must have formed less than a billion years after the big bang, as they are visible today in the form of bright quasars at redshift larger than six. Their early…
Black holes cannot be seen directly since they absorb light and emit none, the very quality which earned them their name. We suggest that black holes may be seen indirectly through a chaotic defocusing of light. A black hole can capture…