36,399 research outputs found
Turbulence and turbulent mixing in natural fluids
Turbulence and turbulent mixing in natural fluids begins with big bang
turbulence powered by spinning combustible combinations of Planck particles and
Planck antiparticles. Particle prograde accretions on a spinning pair releases
42% of the particle rest mass energy to produce more fuel for turbulent
combustion. Negative viscous stresses and negative turbulence stresses work
against gravity, extracting mass-energy and space-time from the vacuum.
Turbulence mixes cooling temperatures until strong-force viscous stresses
freeze out turbulent mixing patterns as the first fossil turbulence. Cosmic
microwave background temperature anisotropies show big bang turbulence fossils
along with fossils of weak plasma turbulence triggered as plasma photon-viscous
forces permit gravitational fragmentation on supercluster to galaxy mass
scales. Turbulent morphologies and viscous-turbulent lengths appear as linear
gas-proto-galaxy-clusters in the Hubble ultra-deep-field at z~7. Proto-galaxies
fragment into Jeans-mass-clumps of primordial-gas-planets at decoupling: the
dark matter of galaxies. Shortly after the plasma to gas transition,
planet-mergers produce stars that explode on overfeeding to fertilize and
distribute the first life.Comment: 23 pages 12 figures, Turbulent Mixing and Beyond 2009 International
Center for Theoretical Physics conference, Trieste, Italy. Revision according
to Referee comments. Accepted for Physica Scripta Topical Issue to be
published in 201
Do micro brown dwarf detections explain the galactic dark matter?
Context: The baryonic dark matter dominating the structures of galaxies is
widely considered as mysterious, but hints for it have been in fact detected in
several astronomical observations at optical, infrared, and radio wavelengths.
We call attention to the nature of galaxy merging, the observed rapid
microlensing of a quasar, the detection of "cometary knots" in planetary
nebulae, and the Lyman-alpha clouds as optical phenomena revealing the compact
objects. Radio observations of "extreme scattering events" and "parabolic arcs"
and microwave observations of "cold dust cirrus" clouds are observed at 15 - 20
K temperatures are till now not considered in a unifying picture. Aims: The
theory of gravitational hydrodynamics predicts galactic dark matter arises from
Jeans clusters that are made up of almost a trillion micro brown dwarfs (mBDs)
of earth weight. It is intended to explain the aforementioned anomalous
observations and to make predictions within this framework. Methods: We employ
analytical isothermal modeling to estimate various effects. Results: Estimates
of their total number show that they comprise enough mass to constitute the
missing baryonic matter. Mysterious radio events are explained by mBD pair
merging in the Galaxy. The "dust" temperature of cold galaxy halos arises from
a thermostat setting due to a slow release of latent heat at the 14 K gas to
solid transition at the mBD surface. The proportionality of the central black
hole mass of a galaxy and its number of globular clusters is explained. The
visibility of an early galaxy at redshift 8.6 is obvious with most hydrogen
locked up in mBDs. Conclusions: Numerical simulations of various steps would
further test the approach. It looks promising to redo MACHO searches against
the Magellanic clouds.Comment: 12 pages A&A tex, 3 pdf figure
The Mass Function of Primordial Rogue Planet MACHOs in quasar nanolensing
The recent Sumi et al (2010, 2011) detection of free roaming planet mass
MACHOs in cosmologically significant numbers recalls their original detection
in quasar microlening studies (Schild 1996, Colley and Schild 2003). We
consider the microlensing signature of such a population, and find that the
nano-lensing (microlensing) would be well characterized by a statistical
microlensing theory published previously by Refsdal and Stabel (1991).
Comparison of the observed First Lens microlensing amplitudes with the
theoretical prediction gives close agreement and a methodology for determining
the slope of the mass function describing the population. Our provisional
estimate of the power law exponent in an exponential approximation to this
distribution is where a Salpeter slope is 2.35.Comment: 12 pages, 1 figur
Gravitational hydrodynamics of large scale structure formation
The gravitational hydrodynamics of the primordial plasma with neutrino hot
dark matter is considered as a challenge to the bottom-up cold dark matter
paradigm. Viscosity and turbulence induce a top-down fragmentation scenario
before and at decoupling. The first step is the creation of voids in the
plasma, which expand to 37 Mpc on the average now. The remaining matter clumps
turn into galaxy clusters. Turbulence produced at expanding void boundaries
causes a linear morphology of 3 kpc fragmenting protogalaxies along vortex
lines. At decoupling galaxies and proto-globular star clusters arise; the
latter constitute the galactic dark matter halos and consist themselves of
earth-mass H-He planets. Frozen planets are observed in microlensing and
white-dwarf-heated ones in planetary nebulae. The approach also explains the
Tully-Fisher and Faber-Jackson relations, and cosmic microwave temperature
fluctuations of micro-Kelvins.Comment: 6 pages, no figure
Instrumentation for Biological Research, Volume I, Sections 1 to 3 Final Report, Nov. 9, 1964 - Mar. 31, 1966
Bioinstrumentation for controlling and measuring parameters interacting with biological syste
Why don't clumps of cirrus dust gravitationally collapse?
We consider the Herschel-Planck infrared observations of presumed
condensations of interstellar material at a measured temperature of
approximately 14 K (Juvela et al., 2012), the triple point temperature of
hydrogen. The standard picture is challenged that the material is cirrus-like
clouds of ceramic dust responsible for Halo extinction of cosmological sources
(Finkbeiner, Davis, and Schlegel 1999). Why would such dust clouds not collapse
gravitationally to a point on a gravitational free-fall time scale of
years? Why do the particles not collide and stick together, as is fundamental
to the theory of planet formation (Blum 2004; Blum and Wurm, 2008) in pre-solar
accretion discs? Evidence from 3.3 m and UIB emissions as well as ERE
(extended red emission) data point to the dominance of PAH-type macromolecules
for cirrus dust, but such fractal dust will not spin in the manner of rigid
grains (Draine & Lazarian, 1998). IRAS dust clouds examined by Herschel-Planck
are easily understood as dark matter Proto-Globular-star-Cluster (PGC) clumps
of primordial gas planets, as predicted by Gibson (1996) and observed by Schild
(1996).Comment: 8 pages, 2 figures, Conference FQMT'1
Metastable liquid-liquid coexistence and density anomalies in a core-softened fluid
Linearly-sloped or `ramp' potentials belong to a class of core-softened
models which possess a liquid-liquid critical point (LLCP) in addition to the
usual liquid-gas critical point. Furthermore they exhibit thermodynamic
anomalies in the density and compressibility, the nature of which may be akin
to those occurring in water. Previous simulation studies of ramp potentials
have focused on just one functional form, for which the LLCP is
thermodynamically stable. In this work we construct a series of ramp
potentials, which interpolate between this previously studied form and a
ramp-based approximation to the Lennard-Jones (LJ) potential. By means of Monte
Carlo simulation, we locate the LLCP, the first order high density liquid
(HDL)-low density liquid (LDL) coexistence line, and the line of density maxima
for a selection of potentials in the series. We observe that as the LJ limit is
approached, the LLCP becomes metastable with respect to freezing into a
hexagonal close packed crystalline solid. The qualitative nature of the phase
behaviour in this regime shows a remarkable resemblance to that seen in
simulation studies of accurate water models. Specifically, the density of the
liquid phase exceeds that of the solid; the gradient of the metastable LDL-HDL
line is negative in the pressure (p)-temperature (T) plane; while the line of
density maxima in the p-T plane has a shape similar to that seen in water and
extends well into the {\em stable} liquid region of the phase diagram. As such,
our results lend weight to the `second critical point' hypothesis as an
explanation for the anomalous behaviour of water.Comment: 7 pages, 8 figure
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