Related papers: Primordial Planet Formation
In a recent paper we had discussed possibility of DM at high redshifts forming primordial planets composed entirely of DM to be one of the reasons for not detecting DM (as the flux of ambient DM particles would be consequently reduced). In…
Primordial, or Pop III, supernovae (SNe) were the first, great nucleosynthetic engines in the Universe, forging the heavy elements required for the later formation of planets, and life. Past studies suggest that the rise of planet formation…
We hypothesise that planets are made by tidal downsizing of migrating giant planet embryos. The proposed scheme for planet formation consists of these steps: (i) a massive young protoplanetary disc fragments at R ~ several tens to hundreds…
The physical and chemical conditions in young protoplanetary disks set the boundary conditions for planet formation. Although the dust in disks is relatively easily detected as a far-IR photometric ``excess'' over the expected photospheric…
Brown dwarfs and very low mass stars are a significant fraction of stars in our galaxy, and they are interesting laboratories to investigate planet formation in extreme conditions of low temperature and densities. In addition, the dust…
The first stars in the Universe are predicted to have been much more massive than the Sun. Gravitational condensation accompanied by cooling of the primordial gas due to molecular hydrogen, yields a minimum fragmentation scale of a few…
I discuss the role that disc fragmentation plays in the formation of gas giant and terrestrial planets, and how this relates to the formation of brown dwarfs and low-mass stars, and ultimately to the process of star formation. Protostellar…
The first stars in the universe form inside $\sim 10^6 M_\odot$ dark matter (DM) haloes whose initial density profiles are laid down by gravitational collapse in hierarchical structure formation scenarios. During the formation of the first…
An unsolved issue in the standard core accretion model for gaseous planet formation is how kilometre-sized planetesimals form from, initially, micron-sized dust grains. Solid growth beyond metre sizes can be difficult both because the…
We developed a three-dimensional 2-level hierarchical cosmological code with a realistic and robust treatment of multi-species non-equilibrium ionization and radiative cooling processes, and use it to investigate primordial star forming…
The nature of the first generation of stars in the Universe remains largely unknown. Observations imply the existence of massive primordial stars early in the history of the universe, and the standard theory for the growth of cosmic…
Was the primordial universe turbulent or non-turbulent soon after the Big Bang? How did the hydrodynamic state of the early universe affect the formation of structure from gravitational forces, and how did the formation of structure by…
Dark matter appears in two forms as a consequence of the fluid mechanics of self-gravitational condensation. Condensation occurs primarily on non-acoustic nuclei rather than on the acoustic nuclei of the Jeans (1902) criterion, leading to a…
Primordial star formation appears to result in stars at least an order of magnitude more massive than modern star formation. It has been proposed that the transition from primordial to modern initial mass functions occurs due to the onset…
The first bound star-forming systems in the universe are predicted to form at redshifts of about 30 and to have masses of the order of 10^6 M_sun. Although their sizes and masses are similar to those of present star-forming regions, their…
Observations of quasar microlensing by Schild 1996 show the baryonic dark matter BDM of galaxies is micro-brown-dwarfs, primordial hydrogen-helium planets formed at the plasma to gas transition 10^13 seconds, in trillion-planet clumps…
The initial conditions, physics, and outcome of planet formation are now constrained by detailed observations of protoplanetary disks, laboratory experiments, and the discovery of thousands of extrasolar planetary systems. These…
Many questions in physical cosmology regarding the thermal history of the intergalactic medium, chemical enrichment, reionization, etc. are thought to be intimately related to the nature and evolution of pregalactic structure. In particular…
Recent discoveries of extrasolar planets at small orbital radii, or with significant eccentricities, indicate that interactions between massive planets and the disks of gas and dust from which they formed are vital for determining the final…
Massive cores of the giant planets are thought to have formed in a gas disk by accretion of pebble-size particles whose accretional cross-section is enhanced by aerodynamic gas drag [1][2]. A commonly held view is that the terrestrial…