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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 703 records · Page 39
All sourcesNASA NTRSDOE OSTI
NASA NTRS1969

Multifluid cosmologies

Coordinate system for synthesizing previous work on multifluid cosmologies, investigating noninteracting mixtures of multicomponent fluids

Hughston, L. P.↗
NASA NTRS1969

Quantum cosmology. I

Hamiltonian methods applied to homogeneous cosmological models, obtaining Einstein equations, passing to quantum theory by imposing canonical commutation relations

Misner, C. W.↗
NASA NTRS1971

Hamiltonian cosmology

Polynomial Hamiltonian for type VIII and IX vacuum cosmologies, suggesting quantized versions involving fluctuations of 3-space signature and topology

Estabrook, F. B.↗
NASA NTRS1972

Galaxy formation from annihilation-generated supersonic turbulence in the baryon-symmetric big-bang cosmology and the gamma ray background spectrum

Following the big-bang baryon symmetric cosmology of Omnes, the redshift was calculated to be on the order of 500-600. It is show that, at these redshifts, annihilation pressure at the boundaries between regions of matter and antimatter drives large scale supersonic turbulence which can trigger galaxy formation. This picture is consistent with the gamma-ray background observations discussed previously. Gravitational binding of galaxies then occurs at a redshift of about 70, at which time vortical turbulent velocities of about 3 x 10 to the 7th power cm/s lead to angular momenta for galaxies comparable with measured values.

Stecker, F. W.↗
NASA NTRS1971

Possible evidence for the existence of antimatter on a cosmological scale in the universe.

Initial results of a detailed calculation of the cosmological gamma-ray spectrum from matter-antimatter annihilation in the universe. The similarity between the calculated spectrum and the present observations of the gamma-ray background spectrum above 1 MeV suggests that such observations may be evidence of the existence of antimatter on a large scale in the universe.

Stecker, F. W.↗
NASA NTRS1972

Curved space cosmological bounds on the time variation of G.

Additional quantitative and revealing arguments are given in favor of author's previous suggestion (1971) that the introduction of pressure results in a decrease in the theoretical upper bound on the time variation of G, as predicted by the Brans-Dicke theory (1961) for Friedmann-type expanding cosmologies in flat space, and that this suggestion holds in curved spaces as well. Moreover, it is shown that the curvature contribution to G is of the same order of magnitude as the flat space contribution and adds to it or subtracts from it for positive or negative curvatures respectively.

Morganstern, R. E.↗