相关论文: The primordial explosion of a false white hole fro…

Using a new kind of 5D Ricci-flat canonical metric, we obtain by a static foliation an effective 4D Schwarzschild-de Sitter hypersurface. We examine some particular initial conditions which could be responsible for the inflationary…

We develop a stochastic approach to study scalar field fluctuations of the inflaton field in an early inflationary universe with a black-hole (BH), which is described by an effective 4D SdS metric. Considering a 5D Ricci-flat SdS static…

We explore the possibility that spacetime horizons in 4D general relativity can be treated as manifestations of higher dimensions that induce fields on our 4D spacetime. In this paper we discuss the black hole event horizon, as an example…

Primordial black holes can be produced by a long range attractive fifth force stronger than gravity, mediated by a light scalar field interacting with nonrelativistic "heavy" particles. As soon as the energy fraction of heavy particles…

Using a previously introduced model in which the expansion of the universe is driven by a single scalar field subject to gravitational attraction induced by a white hole during the expansion (from a 6D vacuum state), we study the origin of…

A central supermassive black hole (SMBH) with a mass $10^6-10^9 M_\odot$ appears to be a common feature in nearby galaxies and the likely power source in quasars and active galactic nuclei. We demonstrate that the formation of a central…

The origin and evolution of supermassive black holes (SMBHs) in our universe have sparked controversy. In this study, we explore the hypothesis that some of these black holes may have seeded from the direct collapse of dark energy domains…

We propose that the growth of supermassive black holes is associated mainly with brief episodes of highly super-Eddington infall of gas ("hyperaccretion"). This gas is not swallowed in real time, but forms an envelope of matter around the…

Black holes are extreme expressions of gravity. Their existence is predicted by Einstein's theory of general relativity and is supported by observations. Black holes obey quantum mechanics and evaporate spontaneously. Here it is shown that…

Recent James Webb Space Telescope observations of high-redshift massive galaxy candidates have initiated renewed interest in the important mystery around the formation and evolution of our Universe's largest supermassive black holes…

Several different approaches to quantum gravity suggest the effective dimension of spacetime reduces from four to two near the Planck scale. In light of such evidence, this letter re-examines the thermodynamics of primordial black holes…

We investigate a new mechanism to create large curvature perturbations on small scales due to parameter resonance in a single-field inflationary model with a small periodic structure upon the potential. After reentering the horizon, the…

There is controversy surrounding the origin and evolution of our universe's largest supermassive black holes (SMBHs). In this study, we consider the possibility that some of these black holes formed from the direct collapse of primordial…

Scalar condensates with large expectation values can form in the early universe, for example, in theories with supersymmetry. The condensate can undergo fragmentation into Q-balls before decaying. If the Q-balls dominate the energy density…

We study the Hawking evaporation of a class of black hole solutions in dRGT massive gravity, in which the graviton mass gives rise to an effective negative cosmological constant. We found that the effective emission surface can be either…

We explore the possibility of explaining dark matter through six-dimensional (6D) primordial black holes (PBHs) in a theory with two extra dimensions. Interestingly, in this scenario the fundamental energy scale is of the order of $\sim 10$…

We study the evaporation of black holes in space-times with extra dimensions of size L. We first obtain a description which interpolates between the expected behaviors of very large and very small black holes and then show that the…

Several anomalies of black hole thermodynamics are resolved if one accepts hints from semi classical theory that in regions of strong gravity the energy density of the vacuum can become substantially negative. This leads to a picture of the…

In this brief note, we investigate some possible experimental consequences of the de-Sitter or Anti-de-Sitter background spacetime structure for d-dimensional evaporating black holes. Possible observational signatures in Large Hadron…

It is shown that primordial black holes (PBHs) of masses M > 5x10^14 g are able to absorb white dwarfs (WD) completely for the time of their existence, giving rise to formation of black holes of WD mases. The WD absorption is accompanied by…