相关论文: Large-amplitude isothermal fluctuations and high-d…

Isocurvature fluctuations, where the relative number density of particle species spatially varies, can be generated from initially adiabatic, or curvature, fluctuations if the various species fall out of or were never in thermal…

Scale-invariant fluctuations and cold dark matter could originate from two different modes of a single scalar field, fluctuations from massless Goldstone oscillations and matter from massive Higgs modes. Matching the fluctuations and dark…

It is shown, using quantum field theory in curved spacetime, how the expansion of the universe during inflation produces an aggregate of particles and inflaton vacuum fluctuations at a temperature of 5x10^17GeV and dense enough to make…

We investigate the dynamics of axion-like particle (ALP) dark matter where the field range is enlarged by a monodromy. The monodromy potential allows sufficient production of dark matter also at larger couplings to the Standard Model…

Traditionally the spherical collapse of objects is studied with respect to a uniform background density, yielding the critical over-density $\delta_\mathrm{c}$ as key ingredient to the mass function of virialized objects. Here we…

We present the results of a series of one-dimensional N-body and hydrodynamical simulations which have been used for testing the different clustering properties of baryonic and dark matter in an expanding background. Initial Gaussian random…

We study the spherical collapse of non-top-hat matter fluctuations in the presence of dark energy with arbitrary sound speed. The model is described by a system of partial differential equations solved using a pseudo-spectral method with…

We consider a simple class of models in which the dark matter, X, is coupled to a new gauge boson, phi, with a relatively low mass (m_phi \sim 100 MeV-3 GeV). Neither the dark matter nor the new gauge boson have tree-level couplings to the…

We perform a systematic analysis of dark matter production during post-inflationary reheating. Following the period of exponential expansion, the inflaton begins a period of damped oscillations as it decays. These oscillations and the…

I review the observational data most relevant for large scale structure. These data determine the system of cosmological parameters: the Hubble parameter, densities of various populations of the Universe, parameters characterizing the power…

The primordial matter power spectrum quantifies fluctuations in the distribution of dark matter immediately following inflation. Over cosmic time, over-dense regions of the primordial density field grow and collapse into dark matter halos,…

We assume that dark matter is comprised of axion-like particles (ALPs) generated by the realignment mechanism in the post-inflationary scenario. This leads to isocurvature fluctuations with an amplitude of order one for scales comparable to…

On large scales galaxies and their halos are usually assumed to trace the dark matter with a constant bias and dark matter is assumed to trace the linear density field. We test these assumption using several large N-body simulations with…

The interplay between disorder, quantum fluctuations and dissipation is studied in the random transverse Ising chain coupled to a dissipative Ohmic bath with a real space renormalization group. A typically very large length scale, L*, is…

Fluctuations in the mass and decay rate of a heavy particle which for some period dominates the energy density of the universe are known to lead to adiabatic density perturbations. We show that generically the annihilation cross section of…

We propose a new alternative to the Weakly Interacting Massive Particle (WIMP) paradigm for dark matter. Rather than being determined by thermal freeze-out, the dark matter abundance in this scenario is set by dark matter decay, which is…

In this letter, we explore the phenomenological impact of inflationary gravitational particle production in the physics of Dark Matter (DM). Large-scale DM fluctuations generated during inflation behave as gravitational particles upon their…

Isolated isothermal spheres of N gravitationally interacting points with equal mass are believed to be stable when density contrasts do not exceed 709. That stability limit does, however, not take into consideration fluctuations of…

In the present work, gravitational collapse of an inhomogeneous spherical star model, consisting of inhomogeneous dust fluid (dark matter) in the background of dark energy is considered. The collapsing process is examined first separately…

The large-scale distribution of cold dark matter halos is generally assumed to trace the large-scale distribution of matter. In a universe with multiple types of matter fluctuations, as is the case with massive neutrinos, the relation…