Related papers: Planets and Dark Energy
There is accumulating evidence that the faint end of the galaxy luminosity function might be very different in different locations. The luminosity function might be rising in rich clusters and flat or declining in regions of low density. If…
The formation of stellar clusters dictates the pace at which galaxies evolve, and solving the question of their formation will undoubtedly lead to a better understanding of the Universe as a whole. While it is well known that star clusters…
In this paper, the first in a series on galaxy formation before reionization, we focus on understanding what determines the size and morphology of stellar objects in the first low mass galaxies, using parsec- scale cosmological simulations…
Recent N-body simulations show that the formation of a present-day, galaxy sized dark matter halo in the CDM cosmogony in general consists of an early fast collapse phase, during which the potential associated with a halo is established,…
Evidence is summarized that suggests that when a protogalaxy collapses, a fraction $f$ of its gas fails to heat to the virial temperature, where $f$ is large for haloes less massive than the value $M^*$ associated with $L^*$ galaxies. Stars…
We use a semi-analytic circumstellar disk model that considers movement of the snow line through evolution of accretion and the central star to investigate how gas giant frequency changes with stellar mass. The snow line distance changes…
In currently popular cosmological scenarios -- all variants of the cold dark matter (CDM) cosmogony -- some time beyond a redshift of 15, stars within the numerous small halos that condense with virial temperatures ~1e4 K created the first…
Hubble Space Telescope images of the Helix Planetary Nebula are interpreted using the hydro-gravitational-dynamics theory (HGD) of Gibson 1996-2006. HGD claims that baryonic-dark-matter (BDM) dominates the halo masses of galaxies (Schild…
We generalize the small scale dynamics of the universe by taking into account models with an equation of state which evolves with time, and provide a complete formulation of the cluster virialization attempting to address the nonlinear…
When the cosmic star formation history peaks (z ~ 2), galaxies vigorously fed by cosmic reservoirs are gas dominated and contain massive star-forming clumps, thought to form by violent gravitational instabilities in highly turbulent…
Gaseous giant planet formation is thought to occur in the first few million years following stellar birth. Models predict that giant planet formation carves a deep gap in the dust component (shallower in the gas). Infrared observations of…
We report results from numerical simulations of star formation in the early universe that focus on gas at very high densities and very low metallicities. We argue that the gas in the central regions of protogalactic halos will fragment as…
Optically thin cooling gas at most temperatures above 30K will make condensations by pressure pushing material into cool dense regions. This works without gravity. Cooling condensations will flatten and become planar/similarity solutions.…
We investigate formation mechanisms for icy super-Earth mass planets orbiting at 2-20 AU around 0.1-0.5 solar mass stars. A large ensemble of coagulation calculations demonstrates a new formation channel: disks composed of large…
The first stars form in dark matter halos of masses ~10^6 M_sun as suggested by an increasing number of numerical simulations. Radiation feedback from these stars expels most of the gas from their shallow potential well of their surrounding…
Planetary systems form in gas-dust protoplanetary discs via the growth of solid bodies. In this paper, we show that the most intriguing stage of such growth --- namely, the transformation of 1-10 m boulders into kilometre-sized…
We describe a coagulation model that leads to the rapid formation of super-Earths and the cores of gas giant planets. Interaction of collision fragments with the gaseous disk is the crucial element of this model. The gas entrains small…
Intermediate mass planets, from Super-Earth to Neptune-sized bodies, are the most common type of planets in the galaxy. The prevailing theory of planet formation, core-accretion, predicts significantly fewer intermediate-mass giant planets…
Properties of normal galactic star formation, including the density dependence, threshold density, turbulent scaling relations, and clustering properties, are applied to the formation of galactic bulges. One important difference is that the…
A standard paradigm is now available for the recent evolution (z < 10) of structure on galactic and larger scales. Most of the matter is assumed to be dark and dissipationless and to cluster hierarchically from gaussian initial conditions.…