Related papers: First Structure Formation: A Simulation of Small S…
All commonly considered dark matter scenarios are based on hypothetical particles with small but non-zero thermal velocities and tiny interaction cross-sections. A generic consequence of these attributes is the suppression of small-scale…
The large-scale structure of the Universe formed from initially small perturbations in the cosmic density field, leading to galaxy clusters with up to 10^15 Msun at the present day. Here, we review the formation of structures in the…
In hierarchical cosmologies the evolution of galaxy clustering depends both on cosmological quantities such as Omega and Lambda, which determine how dark matter halos form and evolve, and on the physical processes - cooling, star formation…
We use numerical simulations of critically-closed cold dark matter (CDM) models to study the effects of numerical resolution on observable quantities. We study simulations with up to $256^3$ particles using the particle-mesh (PM) method and…
(abridged) We study high redshift structure formation and reionization in a LCDM universe under the assumption that the spectral power index of primordial density fluctuations is a function of length scale. We adopt a particular formulation…
The standard cold dark matter (CDM) model predicts too many and too dense small structures. We consider an alternative model that the dark matter undergoes two-body decays with cosmological lifetime $\tau$ into only one type of massive…
We used fully cosmological, high resolution N-body + SPH simulations to follow the formation of disk galaxies with a rotational velocity between 140 and 280 Km/sec in a Lambda CDM universe. The simulations include gas cooling, star…
Star formation in high-redshift dwarf galaxies is a key to understand early galaxy evolution in the early Universe. Using the three-dimensional hydrodynamics code GIZMO, we study the formation mechanism of cold, high-density gas clouds in…
The early universe hosted a large population of low-mass virialized "minihalos," that were not massive enough to form stars on their own. While most minihalos were photoevaporated by ionizing photons from star-forming galaxies, these…
High-redshift star-forming galaxies have very different morphologies compared to nearby ones. Indeed, they are often dominated by bright star-forming structures of masses up to $10^{8-9}$ $\mathrm{M}_\odot$ dubbed {\guillemotleft}giant…
The formation of the first galaxies at redshifts z~10-15 signaled the transition from the simple initial state of the universe to one of ever increasing complexity. We here review recent progress in understanding their assembly process with…
We simulate the formation of a low metallicity (0.01 Zsun) stellar cluster in a dwarf galaxy at redshift z~14. Beginning with cosmological initial conditions, the simulation utilizes adaptive mesh refinement and sink particles to follow the…
Current models of the formation of first galaxies predict low masses and faint objects at extremely high redshifts, z=9-15. However, the first observations of this epoch indicate a higher-than-expected number of bright (sometimes massive)…
The properties of nearby galaxies that can be observed in great detail suggest that a better theory rather than cold dark matter (CDM) would describe in a better way a mechanism by which matter is more rapidly gathered into large-scale…
Recent observations from JWST have revealed unexpectedly luminous galaxies, exhibiting stellar masses and luminosities significantly higher than predicted by theoretical models at Cosmic Dawn. In this study, we present a suite of…
The nature of structure formation around the particle free streaming scale is still far from understood. Many attempts to simulate hot, warm, and cold dark matter cosmologies with a free streaming cutoff have been performed with…
We use a high resolution $\Lambda$CDM numerical simulation to calculate the mass function of dark matter haloes down to the scale of dwarf galaxies, back to a redshift of fifteen, in a 50 $h^{-1}$Mpc volume containing 80 million particles.…
We present first results from three-dimensional hydrodynamic simulations of the high redshift formation of dwarf galaxies. The simulations use an Eulerian adaptive mesh refinement technique to follow the non-equilibrium chemistry of…
We present a model for the formation of massive black holes ($\sim 1000 \msun$) due to stellar-dynamical processes in the first stellar clusters formed at early cosmic times ($z\sim10-20$). The high redshift black hole seeds form as a…
We introduce the Ultramarine simulation, an extremely large $N$-body simulation of the structure formation and evolution to redshift 5.5 at which cosmic reionization was just completed. The simulation evolves 2.1 trillion particles within a…