arXiv subjects

Carl H. Gibson

Publications and source records attributed to Carl H. Gibson.

64 records · Page 4Linked to original sources

arXiv1999

Fossil turbulence revisited

A theory of fossil turbulence presented in the 11th Liege Colloquium on Marine turbulence is "revisited" in the 29th Liege Colloquium "Marine Turbulence Revisited". The Gibson (1980) theory applied universal similarity theories of turbulence and turbulent mixing to the vertical evolution of an isolated patch of turbulence in a stratified fluid as it is constrained and fossilized by buoyancy forces. Towed oceanic microstructure measurements of Schedvin (1979) confirmed the predicted universal constants. Universal constants, spectra, hydrodynamic phase diagrams (HPDs) and other predictions of the theory have been reconfirmed by a wide variety of field and laboratory observations. Fossil turbulence theory has many applications; for example, in marine biology, laboratory and field measurements suggest phytoplankton species with different swimming abilities adjust their growth strategies differently by pattern recognition of several days of turbulence-fossil-turbulence dissipation and persistence times above threshold values, signaling a developing surface layer sea change. In cosmology, self-gravitational structure masses are interpreted as fossils of primordial hydrodynamic states.

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arXiv1999

The fluid mechanics of dark matter formation: Why does Jeans's (1902 & 1929) theory fail?

Jeans's (1902 & 1929) linear gravitational instability criterion gives truly spectacular errors in its predictions of cosmological structure formation according to Gibson's (1996) new nonlinear theory. Scales are determined by viscous or turbulent forces, or by diffusivity, at Schwarz length scales L_SV, L_ST, or L_SD, respectively, whichever is larger. By these new criteria, void formation begins in the plasma epoch soon after matter dominates energy, at L approx L_SV = (gamma nu / rho G)^1/2 scales corresponding to protosuperclusters, decreasing to protogalaxies at the plasma-gas transition, where gamma is the rate-of-strain of the expanding universe, nu is the kinematic viscosity, rho is the density, and G is Newton's gravitational constant. Condensation of the primordial gas occurs at mass scales a trillion times less than the Jeans mass to form a `fog' of micro-brown-dwarf (MBD) particles that persist as the galactic baryonic dark matter, as reported by Schild (1996) from quasar-microlensing studies. Nonbaryonic dark matter condensation is prevented by its enormous diffusivity at scales smaller than L_SD = (D^2 /rho G)^1/2, where D is the diffusivity, so it forms outer halos of galaxies, cluster-halos of galaxy clusters, and supercluster-halos.

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arXiv1999

Theory and observations of galactic dark matter

Sir James Jeans's (1902 and 1929) linear, acoustic, theory of gravitational instability gives vast errors for the structure formation of the early universe. Gibson's (1996) nonlinear theory shows that nonacoustic density extrema produced by turbulence are gravitationally unstable at turbulent, viscous, or diffusive Schwarz scales L_ST, L_SV, L_SD, independent of Jeans's acoustic scale L_J. Structure formation began with decelerations of 10^46 kg protosuperclusters in the hot plasma epoch, 13,000 years after the Big Bang, when L_SV decreased to the Hubble (horizon) scale L_H equiv ct, where c is light speed and t is time, giving 10^42 kg protogalaxies just before the cooled plasma formed neutral H-He gas at 300,000 years. In 10^3 years this primordial gas condensed to 10^23 - 10^25 kg L_SV - L_ST scale objects, termed ``primordial fog particles'' (PFPs). Schild (1996) suggested from continuous microlensing of quasar Q0957 + 561 A,B that the mass of the 10^42 kg lens galaxy is dominated by 10^23 - 10^25 kg ``rogue planets ... likely to be the missing mass''. A microlensing event seen at three observatories confirms Schild's (1996) claims, and supports Gibson's (1996) prediction that PFPs comprise most of the dark matter at galactic scales.

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arXiv1999

Intermittency of internal wave shear and turbulence dissipation

It is crucial to understand the extreme intermittency of ocean and lake turbulence and turbulent mixing in order to estimate vertical fluxes of momentum, heat and mass by Osborn-Cox flux-dissipation methods. Vast undersampling errors occur by this method when intermittency is not taken into account. Oceanic turbulence increases intermittency as the result of a self-similar nonlinear cascade covering a wide range of scales, mostly horizontal. Extremely large intermittency factors Ie and Ic measured for Galactic and oceanic turbulence are in the range 3-7. These values are consistent with the third universal similarity hypothesis for turbulence of Kolmogorov (1962) and a length scale range over 3-7 decades from viscous or diffusive to buoyancy or Coriolis force domination, where the measured universal intermittency constant m_u = 0.44, Gibson (1991a), is a result of singularities in multifractal turbulence dissipation networks and their degeneration, Bershadskii and Gibson (1994). Nonlinear cascades of gravitational structure formation produce intermittent lognormal number densities of cosmological objects for the same reasons.

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arXiv1999

A fluid mechanical explanation of dark matter

Matter in the universe has become ``dark'' or ``missing'' through misconceptions about the fluid mechanics of gravitational structure formation. Gravitational condensation occurs on non-acoustic density nuclei at the largest Schwarz length scale L_{ST}, L_{SV}, L_{SM}, L_{SD} permitted by turbulence, viscous, or magnetic forces, or by the fluid diffusivity. Non-baryonic fluids have diffusivities larger (by factors of trillions or more) than baryonic (ordinary) fluids, and cannot condense to nucleate baryonic galaxy formation as is usually assumed. Baryonic fluids begin to condense in the plasma epoch at about 13,000 years after the big bang to form proto-superclusters, and form proto-galaxies by 300,000 years when the cooling plasma becomes neutral gas. Condensation occurs at small planetary masses to form ``primordial fog particles'' from nearly all of the primordial gas by the new theory, Gibson (1996), supporting the Schild (1996) conclusion from quasar Q0957+651A,B microlensing observations that the mass of the lens galaxy is dominated by ``rogue planets ... likely to be the missing mass''. Non-baryonic dark matter condenses on superclusters at scale L_{SD} to form massive super-halos.

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arXiv1999

Dark matter formation at Schwarz scales: primordial fog particles and WIMP superhalos

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 very different scenario for structure formation. Viscous forces at 10^12 s (30,000 y) after the big bang permit decelerations of 10^47 kg protosupercluster plasma masses, and 10^42 kg protogalaxy masses at 10^13 s (300,000 y). Then gas formed, and all the baryonic universe became a "primordial fog" of 10^23 kg particles at the viscous Schwarz scale: 100% dark matter. Some of these H-He objects have collected to form stars, but most persist as dark dwarfs in galaxy halos. They manifest themselves in quasar microlensing observations as "rogue planets", Schild (1996), "dark galaxies", Hawkins (1996), and as comets "brought out of cold storage", O'Dell and Handron (1996). Non-baryonic WIMP fluids are superviscous, with large viscous Schwarz scales, and condense slowly to form most of the dark matter of galaxy superclusterhalos and clusterhalos.

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arXiv1999

Dark matter at viscous-gravitational Schwarz scales: theory and observations

The Jeans criterion for the minimum self-gravitational condensation scale is extended to include the possibility of condensation on non-acoustic density nuclei at Schwarz scales, where structure formation begins in the plasma epoch at proto-supercluster masses about 10,000 years after the Big Bang, decreasing to galaxy masses at 300,000 years. Then the plasma universe became relatively inviscid gas and condensed to 10^23-26 kg "primordial fog particle" (PFP) masses. Baryonic dark matter by this theory should be mostly non-aggregated PFPs that persist in galactic halos. Schild (1996) suggests from quasar Q0957+561 microlensing that "rogue planets" are "likely to be the missing mass" of the lens galaxy. Non-baryonic dark matter composed of weakly interacting massive particles (WIMPs) should condense slowly at large viscous Schwarz scales to form galaxy supercluster halos, and massive galaxy cluster halos as observed by Tyson and Fischer (1995) for the rich galaxy cluster Abel 1689.

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arXiv1999

Kolmogorov Similarity Hypotheses for Scalar Fields: Sampling Intermittent Turbulent Mixing in the Ocean and Galaxy

Kolmogorov's three universal similarity hypotheses are extrapolated to describe scalar fields like temperature mixed by turbulence. By the analogous Kolmogorov third hypothesis for scalars, temperature dissipation rates chi averaged over lengths r > L_K should be lognormally distributed with intermittency factors I that increase with increasing turbulence energy length scales L_O as I_chi-r = m_T ln(L_O/r). Tests of Kolmogorovian velocity and scalar universal similarity hypotheses for very large ranges of turbulence length and time scales are provided by data from the ocean and the Galactic interstellar medium. The universal constant for turbulent mixing intermittency m_T is estimated from oceanic data to be 0.44+-0.01, which is remarkably close to estimates for Kolmogorov's turbulence intermittency constant m_u of 0.45+-0.05 from Galactic as well as atmospheric data. Extreme intermittency complicates the oceanic sampling problem, and may lead to quantitative and qualitative undersampling errors in estimates of mean oceanic dissipation rates and fluxes. Intermittency of turbulence and mixing in the interstellar medium may be a factor in the formation of stars.

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arXiv1999

Turbulence in the Ocean, Atmosphere, Galaxy, and Universe

Flows in natural bodies of fluid often become turbulent, with eddy-like motions dominated by inertial-vortex forces. Buoyancy, Coriolis, viscous, self-gravitational, electromagnetic, and other force constraints produce a complex phase space of wave-like hydrodynamic states that interact with turbulence eddies, masquerade as turbulence, and preserve information about previous hydrodynamic states as fossil turbulence. Evidence from the ocean, atmosphere, galaxy and universe are compared with universal similarity hypotheses of Kolmogorov (1941, 1962) for turbulence velocity u, and extensions to scalar fields q like temperature mixed by turbulence. Information about previous hydrodynamic states is preserved by Schwarz viscous and turbulence lengths and masses of self-gravitating condensates. Viscous-gravitational formation occurred 10^4-10^5 y after the Big Bang for supercluster, cluster, and then galaxy masses of the plasma, producing the first turbulence. Condensation after plasma neutralization of the H-4He gas was to a primordial fog of sub-solar particles that persists today in galactic halos as "dark matter". These gradually formed all stars, star clusters, etc. (humans!) within.

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arXiv1999

Turbulent mixing, diffusion and gravity in the formation of cosmological structures: the fluid mechanics of dark matter

The theory of gravitational structure formation in astrophysics and cosmology is revised based on real fluid behavior and turbulent mixing theory. Gibson's 1996-1998 theory balances fluid mechanical forces with gravitational forces and density diffusivity with gravitational diffusivity at critical viscous, turbulent, magnetic, and diffusion length scales termed Schwarz scales L_SX. Condensation and void formation occurs on non-acoustic density nuclei produced by turbulent mixing for scales L>=L_SXmax rather than on sound wave crests and troughs for L>=L_J as required by Jeans's 1902 linear acoustic theory. Schwarz scales L_SX = L_SV, L_ST, L_SM, or L_SD may be smaller or larger than Jeans's scale L_J. Thus, a very different "nonlinear" cosmology emerges to replace the currently accepted "linear" cosmology. According to the new theory, most of the inner halo dark matter of galaxies consists of planetary mass objects that formed soon after the plasma to neutral gas transition 300,000 years after the Big Bang. These objects are termed primordial fog particles (PFPs) and provide an explanation for Schild's 1996 "rogue planets ... likely to be the missing mass" of his observed quasar-lens galaxy, inferred from the twinkling frequencies of both quasar images and their phased difference.

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