Related papers: Cosmological pressure fluctuations and spatial exp…
On the basis of the previously formulated mathematical model of a statistical system with scalar interaction of fermions and the theory of gravitational-scalar instability of a cosmological model based on a one-component statistical system…
We use the wide-used \textsf{Einstein Toolkit} to solve the Einstein constraints and then simulate the expansion of primordial black hole lattices (PBHLs) with different value of $f_{\mathrm{PBH}}$ and $m_{\mathrm{PBH}}$. We find that…
We report on a novel phenomenon of the resonance effect of primordial density perturbations arisen from a sound speed parameter with an oscillatory behavior, which can generically lead to the formation of primordial black holes in the early…
In this paper we address the issue of the origin of some observational properties of the galactic globular cluster system. After a preliminary study of some general properties of the main evolutionary processes, we investigate the evolution…
The production of a stochastic background of gravitational waves is a fundamental prediction of any cosmological inflationary model. The features of such a signal encode unique information about the physics of the Early Universe and beyond,…
We use a semianalytical approach and a CDM cosmological model to study the gravitational collapse and virialization, the structure, as well as the global and statistical properties of isolated dark matter galactic halos which emerge from…
Based on the previously formulated theory of spherical perturbations in the cosmological medium of self-gravitating scalarly charged fermions with the Higgs scalar interaction and the similarity properties of such models, the formation of…
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…
During the inflationary phase of the early universe, quantum fluctuations in the vacuum generate particles as they stretch beyond the Hubble length. These fluctuations are thought to result in the density fluctuations and gravitational…
We consider the early universe at temperatures close to the fundamental scale of gravity (M_D << M_Planck) in models with extra dimensions. At such temperatures a small fraction of particles will experience transplanckian collisions that…
We speculate that the early Universe was inside a primordial black hole. The interior of the the black hole is a dS background and the two spacetimes are separated on the surface of black hole's event horizon. We argue that this picture…
In this short review, we discuss how Earth's climatological and geological history and also how the shadows of galactic black holes might reveal our Universe's past evolution. Specifically we point out that a pressure singularity that…
Primordial black holes may have formed in the radiative era of the early Universe from the collapse of large enough amplitude perturbations of the metric. These correspond to non linear energy density perturbations characterized by an…
Several processes in the early universe might lead to the formation of primordial black holes with different masses. These black holes would interact with the cosmic plasma through accretion and emission processes. Such interactions might…
The physics of primordial black holes can be affected by the non-Gaussian statistics of the density fluctuations that generate them. Therefore, it is important to have good theoretical control of the higher-order correlation functions for…
We consider the formation of primordial black holes (PBHs), during the radiation-dominated Universe, generated from the collapse of super-horizon curvature fluctuations that are overlapped with others on larger scales. Using a set of…
We study the first law of black hole thermodynamics in the presence of surrounding gravitational fields and argue that variations of these fields are naturally incorporated in the first law by defining gravitational tension or gravitational…
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…
We discuss the various ways in which primordial black holes may have formed in the early Universe and how the effects of such black holes can be used to place constraints on cosmological models. We show that such constraints may be severely…
The Universe may pass through an effectively matter-dominated epoch between inflation and Big Bang Nucleosynthesis during which gravitationally bound structures can form on subhorizon scales. In particular, the inflaton field can collapse…