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NASA NTRS1972

Closed anisotropic cosmological models.

Derivation of a new exact solution to Einstein's equations representing homogeneous nonisotropic cosmological models of a closed universe containing electromagnetic and scalar fields. This solution reduces to a generalization of Brill's electromagnetic universe when the scalar field vanishes, and to the Taub-NUT-M space when both these fields vanish. The solutions also satisfy the scalar tensor equations and represent a universe containing electromagnetic fields and a source-free solution to the scalar-tensor equations representing a closed universe.

Batakis, N.↗

NASA NTRS1973

Gamma-ray Background Spectrum and Annihilation Rate in the Baryon-symmetric Big-bang Cosmology

An attempt was made to acquire experimental information on the problem of baryon symmetry on a large cosmological scale by observing the annihilation products. Data cover absorption cross sections and background radiation due to other sources for the two main products of annihilation, gamma rays and neutrinos. Test results show that the best direct experimental test for the presence of large scale antimatter lies in the gamma ray background spectrum between 1 and 70 MeV.

Puget, J. L.↗

NASA NTRS1974

A search for a cosmological component of the soft X-ray background in the direction of M31

Results of an experiment to search for absorption of the soft diffuse X-ray background by M31, the Andromeda Nebula, are presented. Both X-ray and 21-cm observations were obtained with high spatial resolution; the X-ray detector had a 2-degree field of view, and the 21-cm data were taken with 20-minute resolution. The results establish that at least 48 percent of the soft X-ray flux has a local source, but that the remainder may be of distant origin and therefore of cosmological significance.

Margon, B.↗

NASA NTRS1974

Oparin and the origin of life - Cosmological considerations

The question of the origin of life is examined on a cosmological scale from early observations made by Oparin. Even by a comparison of the amount of data presently available from telescopic and spacecraft observations Oparin's conclusions have been confirmed. The concept of panspermia is rejected and details of the role of carbon on earth are presented. Formation of C2, CN and CH is explained and various aspects of the atmospheres of planets are considered. Finally, the origin of amides, amines and other nitrogenous derivatives from hydrocarbons is discussed.

Young, R. S.↗

NASA NTRS1975

Spectrophotometry of faint cluster galaxies and the Hubble diagram - An approach to cosmology

New spectrophotometric data are presented for large-redshift galaxies in clusters. A new approach to aperture corrections and the analysis of the Hubble diagram is outlined, including the explicit incorporation of evolutionary effects. The importance of selection effects on the usual methods of analysis are in principle overcome in the analysis, although the heterogeneity of the sample still makes conclusions about cosmology slightly suspect. Formal values of the deceleration parameter are derived under several sets of assumptions, yielding results between +0.33 and -1.27 with formal standard deviations of order 0.7.

Gunn, J. E.↗

NASA NTRS1976

Determination of the cosmological rate of change of G and the tidal accelerations of earth and moon from ancient and modern astronomical data

The theory and numerical analysis of ancient astronomical observations (1374 to 1715) are combined with modern data in a simultaneous solution for: the tidal acceleration of the lunar longitude; the observed apparent acceleration of the earth's rotation; the true nontidal geophysical part of this acceleration; and the rate of change in the gravitational constant. Provided are three independent determinations of a rate of change of G consistent with the Hubble Constant and a near zero nontidal rotational acceleration of the earth. The tidal accelerations are shown to have remained constant during the historical period within uncertainties. Ancient and modern solar system data, and extragalactic observations provided a completely consistent astronomical and cosmological scheme.

Muller, P. M.↗

NASA NTRS1975

Exact solution of the Lifshitz equations governing the growth of fluctuations in cosmology

The exact solution of the Lifshitz equations governing the cosmological evolution of an initial fluctuation is presented. Lifshitz results valid for squares of the sound velocity equal to zero and 1/3 are extended in closed form to any equation of state where the pressure equals the total energy density times the square of the sound velocity. The solutions embody all the results found previously for special cases of the square of the sound velocity. It is found that the growth of any initial fluctuation is only an exponential function of time with an exponent of not more than 4/3 and is insufficient to produce galaxies unless the initial fluctuation is very large. A possible way to produce very large initial fluctuations by modifying the equation of state by including gravitational interactions is also examined. It is found that a phase transition can occur at baryonic density of 1 nucleon per cubic Planck length or equivalently, at a time of about 10 to the -43rd power sec. At those early times, the masses allowed by causality requirements are too small to be of interest in galaxy formation.

Adams, P. J.↗

NASA NTRS1976

White dwarfs, the Galaxy and Dirac's cosmology

The additive and multiplicative versions of Dirac's cosmological hypothesis relating the gravitational constant variation with elapsed time and number of particles populating the universe is invoked to account for the deficiency or absence of white dwarfs fainter than about 0.0001 solar luminosity. An estimate is made of white dwarf luminosity in accordance with the two evolutionary models, and it is conjectured that some old white dwarfs with high space velocities may be on the verge of gravitational collapse. Lack of a special mechanism to produce the vast numbers of black holes or other dead stars accounting for 'missing matter' in the vicinity of the sun and in the galactic halo is noted in Dirac's multiplicative model. Results indicate that either Dirac's theory is untenable, or that radiation and heating are of some unknown nature, or that the process of creation of new matter requires a corresponding input of energy.

Stothers, R.↗

NASA NTRS1977

Techniques of Global analysis applied to gravitation theories: A cosmological black hole?

An elementary model of freely falling observers and emitters within a black hole's radius is examined to determine the redshift spectrum reaching a typical observer. The model is independent of scale, the fundamental unit being the radius (mass) of the black hole. The observers/emitters all follow the same kinds of trajectories: radially inward and starting from rest at spatial infinity. The test-particle role is assumed throughout; i.e., the observers/emitters do not themselves contribute to the gravitational field of the system. By means of redshift formulas and luminosity distance to the emitters, a picture of actual redshifts and blueshifts, with their intensities, emerges for an observer within the black hole's radius. No luminosity distances greater than approximately one-half the radius are considered in this particular study; nevertheless, redshifts and blueshifts up to approximately 0.6 are seen in portions of the observer's celestial sphere. An exotic application can be made, as a curiosity, to a black hole the size of the universe, resulting in a particular anisotropic "cosmology."

Debney, G.↗

NASA NTRS1977

Gamma-rays and the case for baryon symmetric big-bang cosmology

Stecker, F. W.↗

NASA NTRS1977

Dirac cosmology

The large numbers hypothesis (LNH) linking the magnitude of large dimensionless ratios in physics (on the order of 10 to the 40th power) to cosmic time is examined. The LNH is checked against evidence on 3K background radiation of the universe and the (log N, log S)-relation for radio galaxies. Earlier criticisms of LNH by Gamow and Teller are examined, and alternative hypotheses put forth by Dicke and Carter (1974) are discussed. The discussion covers: continuous (additive or multiplicative) creation of matter, the Einstein metric and the atomic metric, and general cosmological and local astronomical implications of LNH. LNH is also viewed in relation to solar evolution and pulsar physics.

Canuto, V.↗

NASA NTRS1977

Gamma rays and the case for baryon symmetric big-bang cosmology

The baryon symmetric big-bang cosmologies offer an explanation of the present photon-baryon ratio in the universe, the best present explanation of the diffuse gamma-ray background spectrum in the 1 to 200 MeV range, and a mechanism for galaxy formation. In the context of an open universe model, the value of omega which best fits the present gamma-ray data is omega equals approx. 0.1 which does not conflict with upper limits on Comptonization distortion of the 3K background radiation. In regard to He production, evidence is discussed that nucleosynthesis of He may have taken place after the galaxies were formed.

Stecker, F. W.↗

NASA NTRS1978

Baryon symmetric big-bang cosmology

The framework of baryon-symmetric big-bang cosmology offers the greatest potential for deducing the evolution of the universe as a consequence of physical laws and processes with the minimum number of arbitrary assumptions as to initial conditions in the big-bang. In addition, it offers the possibility of explaining the photon-baryon ratio in the universe and how galaxies and galaxy clusters are formed, and also provides the only acceptable explanation at present for the origin of the cosmic gamma ray background radiation.

Stecker, F. W.↗

NASA NTRS1978

Scale covariant cosmology and the temperature of the earth

Geological data are used as cosmological determinants in a study of the temperature of the early earth (2.3 to 4.5 billion years ago). It is known that the energy output of the sun during that period was on the order of 30-40% lower than at present, and deduced that the mean temperature of the earth should have fallen to as low as 245 K, i.e., below the freezing point of seawater. Strong evidence exists, however, to indicate that algae (therefore liquid water) was present. To reconcile the discrepancies, a model is proposed whereby terrestrial G and M vary. It is further noted that atmosphere H2 may be a better agent than NH3 for producing a greenhouse effect.

Canuto, V.↗

NASA NTRS1978

Baryon symmetric big bang cosmology

Both the quantum theory and Einsteins theory of special relativity lead to the supposition that matter and antimatter were produced in equal quantities during the big bang. It is noted that local matter/antimatter asymmetries may be reconciled with universal symmetry by assuming (1) a slight imbalance of matter over antimatter in the early universe, annihilation, and a subsequent remainder of matter; (2) localized regions of excess for one or the other type of matter as an initial condition; and (3) an extremely dense, high temperature state with zero net baryon number; i.e., matter/antimatter symmetry. Attention is given to the third assumption, which is the simplest and the most in keeping with current knowledge of the cosmos, especially as pertains the universality of 3 K background radiation. Mechanisms of galaxy formation are discussed, whereby matter and antimatter might have collided and annihilated each other, or have coexisted (and continue to coexist) at vast distances. It is pointed out that baryon symmetric big bang cosmology could probably be proved if an antinucleus could be detected in cosmic radiation.

Stecker, F. W.↗

NASA NTRS1978

New trends in cosmology

A review of big-bang cosmology is presented, emphasizing the big-bang model, hypotheses on the origin of galaxies, observational tests of the big-bang model that may be possible with the Large Space Telescope, and the scale-covariant theory of gravitation. Detailed attention is given to the equations of general relativity, the redshift-distance relation for extragalactic objects, expansion of the universe, the initial singularity, the discovery of the 3-K blackbody radiation, and measurements of the amount of deuterium in the universe. The curvature of the expanding universe is examined along with the magnitude-redshift relation for quasars and galaxies. Several models for the origin of galaxies are evaluated, and it is suggested that a model of galaxy formation via the formation of black holes is consistent with the model of an expanding universe. Scale covariance is discussed, a scale-covariant theory is developed which contains invariance under scale transformation, and it is shown that Dirac's (1937) large-numbers hypothesis finds a natural role in this theory by relating the atomic and Einstein units.

Canuto, V. M.↗

NASA NTRS1977

Asteroid surface materials - Mineralogical characterizations and cosmological implications

The theoretical basis for the interpretation of diagnostic spectral features is examined and previous characterizations of asteroid surface materials are considered. A summary is provided of results reported by Gaffey and McCord (1977) who have utilized the most sophisticated interpretive techniques available to interpret the spectral reflectance data of about 65 asteroids for mineralogic and petrologic information. Cosmological implications related to the study of asteroid surface materials are also considered, taking into account source bodies for the meteorites, postaccretionary thermal history, significant factors of asteroid thermal history, and the Apollo and Amor asteroids. It is found that the asteroids exhibit surface materials made up of assemblages of meteoritic minerals. The relative abundance of meteorite types reaching the earth's surface is very different from the population of mineralogic types on asteroid surfaces. The earth-crossing or -approaching asteroids apparently derive from a restricted source region or population which is very strongly depleted in the C2-like assemblages that dominate the belt as a whole.

Gaffey, M. J.↗

NASA NTRS1977

Arguments and evidence concerning non-cosmological redshifts - A partial summary

Theories which imply an unconventional interpretation of the redshifts are examined, taking into account a new theory of cosmology reported by Segal, scenarios in which the redshifts do not arise from the expansion, and studies concerning a possible existence of systematic effects in the distribution of redshifts. Attention is given to rapidly varying QSOs and BL Lac objects, VLBI studies of a number of QSOs and related objects, and physical associations between objects with very different redshifts. It appears that observational evidence concerning these physical associations is the strongest evidence that objects with large noncosmological redshift components exist. On the other hand, there are a number of cases of QSOs close to galaxies at the same redshifts.

Burbidge, G.↗