Related papers: Expanding Microscopic Black Holes
The article summarizes the observational evidence for the existence of massive black holes, as well as the current knowledge about their abundance, their mass and spin distributions, and their cosmic evolution within and together with their…
It was recently suggested that "cosmologically coupled" black holes with masses that increase in proportion to the volume of the Universe might constitute the physical basis of dark energy. We take this claim at face value and discuss its…
Our understanding of space and time is probed to its depths by black holes. These objects, which appear as a natural consequence of general relativity, provide a powerful analytical tool able to examine macroscopic and microscopic…
It was recently claimed that black holes can explain the accelerated expansion of the universe. Here I point out that this claim is based on a confusion about the principle of least action, undermining the link between black holes and dark…
Microscopic black holes explode with their temperature varying inversely as their mass. Such explosions would lead to the highest temperatures in the present universe, all the way to the Planck energy. The possibility that a…
An exact solution representing black holes in an expanding universe is found. The black holes are maximally charged and the universe is expanding with arbitrary equation of state. It is an exact solution of the Einstein-scalar-Maxwell…
Observations have found black holes spanning ten orders of magnitude in mass across most of cosmic history. The Kerr black hole solution is however provisional as its behavior at infinity is incompatible with an expanding universe. Black…
It is suggested that the recently observed size evolution of very massive compact galaxies in the early universe can be explained, if dark matter is in Bose Einstein condensate. In this model the size of the dark matter halos and galaxies…
I begin by summarizing the evidence that there is a close relationship between the evolution of galaxies and supermassive black holes. They evidently share a common fuel source, and feedback from the black hole may be needed to suppress…
The hypothesis that the mass of black holes increases with time according to the same law as the volume of the part of the Universe containing it and therefore the population of BHs is similar to dark energy in its action was recently…
A recent understanding on how quantum effects may affect black-hole evolution opens new scenarios for dark matter, in connection with the presence of black holes in the very early universe. Quantum fluctuations of the geometry allow for…
We examine the production and evolution of microscopic black holes in the early universe in the large extra dimensions scenario. We demonstrate that, unlike in the standard four-dimensional cosmology, in large extra dimensions absorption of…
Black holes are a common feature of the Universe. They are observed as stellar mass black holes spread throughout galaxies and as supermassive objects in their centres. Observations of stars orbiting close to the centre of our Galaxy…
Binary black holes occupy a special place in our quest for understanding the evolution of galaxies along cosmic history. If massive black holes grow at the center of (pre-)galactic structures that experience a sequence of merger episodes,…
A brief overview of the discovery that macroscopic black holes are thermodynamical systems is presented. They satisfy the laws of thermodynamics and are associated with a temperature and an entropy equal to one quarter of their horizon area…
If the cosmological dark matter is primarily in the form of an elementary particle which has cross section and mass for self-interaction having a ratio similar to that of ordinary nuclear matter, then seed black holes (formed in stellar…
Massive black holes are key inhabitants of the nuclei of galaxies. Moreover, their astrophysical relevance has gained significant traction in recent years, thanks especially to the amazing results that are being (or will be) delivered by…
Primordial black holes that survive until the present have been considered as a dark matter candidate. In this paper we argue that primordial 2-2-hole remnants provide a more promising and testable option. 2-2-holes arise in quadratic…
Supermassive black holes have been detected in all galaxies that contain bulge components when the galaxies observed were close enough so that the searches were feasible. Together with the observation that bigger black holes live in bigger…
Black holes are by definition black, and therefore cannot be directly observed by using electromagnetic radiations. Convincing identification of black holes must necessarily depend on the identification of a very specially behaving matter…