Author name code: dicke ADS astronomy entries on 2022-09-14 author:Dicke, Robert H. ------------------------------------------------------------------------ Title: Republication of: The theoretical significance of experimental relativity Authors: Dicke, R. H. Bibcode: 2019GReGr..51...57D Altcode: This republication consists of the introductory section of "The theoretical significance of experimental relativity" (1964). The material itself appeared first as lectures at a Les Houches school. It played a seminal role in stimulating the now rich field of experimental gravitational physics, by surveying earlier experiments and the current and recent work by Dicke and his group, in particular their improved version of the famous Eötvös experiment, and by analysing their theoretical consequences in detail. Future topics for enquiry were pointed out. The paper has been selected by the Editors of General Relativity and Gravitation for re-publication in the Golden Oldies series of the journal. This republication is accompanied by an editorial note written by P. J. E. Peebles and by a brief biography written by M. A. H. MacCallum. Title: Solar oblateness and general relativity (Physical Review Letters 1967) Authors: Dicke, R. H.; Goldenberg, H. M. Bibcode: 1993inas.book...48D Altcode: No abstract at ADS Title: Dirac's Cosmology and Mach's Principle Authors: Dicke, R. H. Bibcode: 1990pcp..book..121D Altcode: No abstract at ADS Title: The Surface Temperature of the Sun and Changes in the Solar Constant Authors: Kuhn, J. R.; Libbrecht, K. G.; Dicke, R. H. Bibcode: 1988Sci...242..908K Altcode: The solar distortion telescope has been used to measure the limb shape and latitude dependence of the limb brightness during the summer months for a 5-year period--a time base sufficient to detect solar cycle trends in the data. Comparison of these observations with spaceborne measurements of the solar constant suggests that a significant part of the solar cycle variation in irradiance is a result of temporal changes in the latitude-dependent surface temperature of the sun. Title: The Phase Variations of the Solar Cycle Authors: Dicke, R. H. Bibcode: 1988SoPh..115..171D Altcode: It has previously been shown that the statistics of the phase fluctuation of the sunspot cycle are compatible with the assumption that the solar magnetic field is generated deep in the Sun by a frequency stable oscillator and that the observed substantial phase fluctuation in the sunspot cycle is due to variation in the time required for the magnetic field to move to the solar surface (Dicke, 1978, 1979). It was shown that the observed phase shifts are strongly correlated with the amplitude of the solar cycle. It is shown here that of two empirical models for the transport of magnetic flux to the surface, the best fit to the data is obtained with a model for which the magnetic flux is carried to the surface by convection with the convection velocity proportional to a function of the solar cycle amplitude. The best fit of this model to the data is obtained for a 12-yr transit time. The period obtained for the solar cycle is T = 22.219 ± 0.032 yr. It is shown that the great solar anomaly of 1760-1800 is most likely real and not due to poor data. Title: On Observing the Absence of an Atom Authors: Dicke, R. H. Bibcode: 1988bqc..book..400D Altcode: No abstract at ADS Title: Cosmic Black-Body Radiation Authors: Dicke, R. H.; Peebles, P. J. E.; Roll, P. G.; Wilkinson, D. T. Bibcode: 1988eur..book..117D Altcode: No abstract at ADS Title: Observations of a Solar Latitude-dependent Limb Brightness Variation: Erratum Authors: Kuhn, J. R.; Libbrecht, K. G.; Dicke, R. H. Bibcode: 1987ApJ...319.1010K Altcode: No abstract at ADS Title: Is the Solar Oblateness Variable? Measurements of 1985 Authors: Dicke, R. H.; Kuhn, J. R.; Libbrecht, K. G. Bibcode: 1987ApJ...318..451D Altcode: The solar oblateness measured in 1985 is Δr = req-rp = 14.6±2.2 arc ms, where the error is only a formal standard deviation assuming normally distributed and uncorrelated errors. The above result is significantly greater than the 1984 value which, in turn, is significantly less than the 1983 and 1966 values. The differences may be physically significant and are consistent with the hypothesis that the oblateness oscillates with the 11.14 yr period of the solar cycle. The data at present only weakly support this hypothesis. Title: Evidence of global circulation currents from solar-limb temperature variations Authors: Kuhn, J. R.; Libbrecht, K. G.; Dicke, R. H. Bibcode: 1987Natur.328..326K Altcode: The temperature distribution in a turbulent rotating photosphere is non-spherical. Dimensional arguments for the Sun suggest that such a temperature modulation may have an amplitude ΔT~ Tv2/Φ~0.1 K, where T is an average temperature (5,700 K) and v2/Φ is the ratio of the rotational kinetic and potential energy density of the photosphere. Detailed calculations1-3 generally support this expectation. Here we report new observations that should help to understand the solar global dynamics problem. From about 1,400 h of solar-limb data obtained during the summers of 1983-85 we find that the solar-limb temperature variation is not spherically symmetric and is ~1 K. Our results also indicate that the limb temperature departs from its expected l = 2 spatial harmonic form and has, at most, a weak dependence on solar cycle. Title: Solar distortion measurements Authors: Dicke, R. H.; Kuhn, J. R. Bibcode: 1987prnc.rept.....D Altcode: Highly accurate solar limb temperature and shape observations were obtained from Mt Wilson using a highly specialized telescope. The solar oblateness appears to fluctuate on a time scale of years. A latitude dependent solar limb temperature variation exists with a temperature amplitude of about 0.6k. This temperature variation is independent of the solar cycle. Oblateness of the Sun in 1983 and Relativity; On the Facular Contrast Near the Solar Limb; Brightness Variation; Another Reason to Search for Solar g-Modes and New Limits from Solar Ellipticity Measurements; Solar Ellipticity Fluctuations Yield No Evidence of g-Modes; The Variable Oblateness of the Sun: Measurements of 1984; Is the Solar Oblateness Variable? Measurements of 1985; More Evidence for a Solar Latitude Dependent Limb Temperature Variation. Title: The Variable Oblateness of the Sun: Measurements of 1984 Authors: Dicke, R. H.; Kuhn, J. R.; Libbrecht, K. G. Bibcode: 1986ApJ...311.1025D Altcode: The solar oblateness measured in 1984 appears to be significantly less than the 1983 value. This is in turn substantially less than the 1966 value. The observations of 1983 and 1984 were made with a modified and improved version of the Princeton Solar Distortion Telescope used in 1966. Its design is discussed. The sources of error and the analysis technique are discussed. The observed changes in oblateness of the sun are believed to be real and significant. Title: New force or thermal gradient in the Eötvös experiment\? Authors: Chu, Shu-Yuan; Dicke, R. H. Bibcode: 1986PhRvL..57.1823C Altcode: Recently Fischbach et al. suggested that the accelerations of various materials to the Earth may be different depending on their compositions, on the basis of their reanalysis of the results of the experiment of Eötvös, Pekár, and Fekete. We find that systematic effects due to thermal gradients can account for the experimental data. Title: Cosmic Black Body Radiation Authors: Dicke, R. H.; Peebles, P. J. E.; Roll, P. G.; Wilkinson, D. T. Bibcode: 1986coco.conf..133D Altcode: No abstract at ADS Title: Solar ellipticity fluctuations yield no evidence of g-modes Authors: Kuhn, J. R.; Libbrecht, K. G.; Dicke, R. H. Bibcode: 1986Natur.319..128K Altcode: Although there have been several claims for the detection of solar g-modes with periods between 2 and 10 hours1-3 and although the present sensitivity of the Princeton Solar Distortion Telescope should allow these low frequency modes to be observed, solar oblateness data from the summers of 1983 and 1984 show no evidence of such oscillations with periods between 1 and 5 hours. In about 250 days (nearly 1,000 hours) of observations, we find no evidence for significant spectral power associated with g-modes. In particular, there is no evidence of a 160.01-min period solar oscillation. Title: Oblateness of the Sun in 1983 and relativity Authors: Dicke, R. H.; Kuhn, J. R.; Libbrecht, K. G. Bibcode: 1985Natur.316..687D Altcode: Measurements of the solar oblateness obtained during 1983 from Mount Wilson, California, yield a value with an upper bound only half of that observed in 1966. This difference may support the conjecture that the solar quadrupole moment slowly oscillates. A knowledge of the character of such an oscillation, if it occurs, would be needed to test Einstein's relativity theory using Mercury's orbital motion. Title: Observations of a Solar Latitude-dependent Limb Brightness Variation Authors: Kuhn, J. R.; Libbrecht, K. G.; Dicke, R. H. Bibcode: 1985ApJ...290..758K Altcode: A small latitude-dependent photospheric excess brightness variation has been observed from 131 days of data obtained with the Princeton Solar Distortion Telescope. Using an analytic model to separate the influence of faculae from the brightness signal, a temperature difference of 0.6 + or - 0.1 K between the poles and the regions at + or - 53 solar latitude was obtained for the summer of 1983, a temperature difference of 0.6 + or - 0.1 K between the poles and the regions at + or - 53 deg solar latitude was obtained for the summer of 1983, with the polar regions being hotter. Title: Observations of a Solar Latitude Dependent Photospheric Brightness Variation Authors: Kuhn, J. R.; Libbrecht, K. G.; Dicke, R. H. Bibcode: 1984BAAS...16..451K Altcode: No abstract at ADS Title: Facular influences on the apparent solar shape Authors: Dicke, R. H.; Kuhn, J. R.; Libbrecht, K. G. Bibcode: 1983Natur.304..326D Altcode: Schatten and Sofia1 have recently reconsidered the question of whether the 1966 solar ellipticity measurements2 were seriously contaminated by excess brightness of faculae near the solar limb3-7. They considered several different functions for the variations of the facular contrast with position relative to the solar limb. With their own facular contrast function, Schatten and Sofia obtain only a small contribution of faculae to the 1966 apparent solar ellipticity, but with the Chapman function they obtain a substantial contribution. New observations of faculae during the summer of 1982 and a novel analytical technique determine a facular contrast which is constant or decreasing towards the limb, consistent with the Schatten and Sophia function but inconsistent with Chapman's function. We show here that the statistical analysis of the 1966 data8 supports this result. We disagree with the earlier conclusion1, that with an acceptable facular contrast function one can obtain ``an acceptable fit to the oblateness measurements'' as a purely facular effect. For 20-30% of the observational days in 1966 only a few small, weak facular patches were present at the limb, but the ellipticity signal was present and it was not reduced in magnitude for those days. Title: Evidence for a distorted solar core rotating with a 12.4-day period Authors: Dicke, R. H. Bibcode: 1983Natur.303..292D Altcode: The periodicity recently discovered in the solar Doppler velocity may be due to an Eddington-Sweet current driven in the photosphere by a distorted gravitational potential rotating rigidly with a synodic period of 12.81+/-0.10 days (12.4 days sidereal). Title: Mercury's Perihelion, from Le Verrier to Einstein Authors: Roseveare, N. T.; Dicke, R. H. Bibcode: 1983AmJPh..51..478R Altcode: No abstract at ADS Title: The Binary Pulsar / PSR1913+16 / a Textbook Example Authors: Taylor, J.; Weisberg, J.; Dicke, R.; Brans, C. Bibcode: 1983S&T....65..325T Altcode: No abstract at ADS Title: The 5-min oscillations of the Sun are incompatible with a rapidly-rotating core Authors: Dicke, R. H. Bibcode: 1982Natur.300..693D Altcode: Hill's suggestion that Einstein's general relativity may be invalid requires a rapidly spinning solar core. The triplet structure observed in the solar 5-minute power spectrum seems incompatible with this rotating core. But the triplet structure can be accounted for as the effect of a magnetically distorted core rotating with a ~12.5-day period. Title: A Magnetic Core in the Sun - the Solar Rotator Authors: Dicke, R. H. Bibcode: 1982SoPh...78....3D Altcode: The previously found solar distortion rotating rigidly and wave-like on the surface with a ∼ 12 day period is interpreted as the shape of the gravitational potential induced by the solar core distorted by an internal magnetic field and rotating rigidly with this period. The distortion does not have a symmetry axis and the necessary magnetic field is not compatible with the axial symmetry required of a quasi-static field locked in the rotating core. It is concluded that if the solar distortion is due to such a process the core is oscillating with a very long period, a toroidal oscillation with a period of the order of years. Title: 1946, The Measurement of Thermal Radiation at Microwave Frequencies Authors: Dicke, R. H. Bibcode: 1982cra..book..106D Altcode: No abstract at ADS Title: 1946, Microwave Radiation from the Sun and Moon Authors: Dicke, R. H.; Beringer, R. Bibcode: 1982cra..book..218D Altcode: No abstract at ADS Title: Seismology and Geodesy of the Sun: Low-Frequency Oscillations Authors: Dicke, R. H. Bibcode: 1981PNAS...78.1989D Altcode: The hourly averages of the solar ellipticity measured from June 13 to Sept. 17, 1966, are analyzed for indications of solar oscillations with periods in excess of 2 hr ν < 0.5 hr-1. Nothing significant is found for frequencies ν > 0.1 hr-1 but for lower frequencies the power spectrum shows a very complex structure containing about 20 strong narrow peaks. The complexity is illusionary. The signal apparently consists of only two frequencies. The complexity is due to aliasing by the window function with its basic 24-hr period, with many observational days missing, and with different numbers of hourly averages for the various observational days. Both signal frequencies are apparently due to odd-degree spherical harmonic oscillations of the sun. Title: Seismology and Geodesy of the Sun: Solar Geodesy Authors: Dicke, R. H. Bibcode: 1981PNAS...78.1309D Altcode: Measurements of the elliptical figure of the sun made in 1966 are analyzed on an hourly basis. This analysis yields an improved measure of the previously found solar distortion, rotating rigidly with a sidereal period of 12.38±0.10 days. It also yields a set of residùals used to search for signals due to low-frequency solar oscillations. Title: Solar Currents and the Magnetic Cycle Authors: Howard, R.; Labonte, B.; Dicke, R. H.; Wilcox, J. Bibcode: 1980SciN..117..245H Altcode: No abstract at ADS Title: Solar luminosity and the sunspot cycle Authors: Dicke, R. H. Bibcode: 1979Natur.280...24D Altcode: Neither sunspots, flares, other solar activity, nor the solar wind, are found to be responsible for the 22-yr solar cycle period found in the [D/H] climate indicator. This period may be due to a periodic variation in solar luminosity induced by a deeply buried magnetic field. Title: The clock inside the Sun. Authors: Dicke, R. H. Bibcode: 1979NewSc..83...12D Altcode: It is suggested that the phase of the solar cycle seems to be locked to the phase of some precisely tuned internal oscillator and that there is apparently a close correlation between the phase error of the sunspot cycle relative to this oscillator and the peak sunspot number. A tentative model involving buoyant magnetic flux tubes is considered which gives a frequency of 0.4460 + or - 0.00007 cycles per year for the internal oscillator. Filtered data based on the Epstein-Yapp statistical indicator are shown to yield a power spectrum with one prominent peak having a frequency of 0.04472 + or - 0.00012 cycles per year, which differs by only 0.27% from the frequency of the solar cycle. A model based on a solar core distorted by a strong toroidal magnetic field is tentatively proposed. Title: Do solar-type stars have magnetic cores? A question of stability. Authors: Dicke, R. H. Bibcode: 1979ApJ...228..898D Altcode: The differentially rotating, stably stratified core expected in new solar-type stars, according to Larson and others, should generate a strong toroidal magnetic field by winding a weak poloidal magnetic field. It is shown that such a toroidal magnetic field (with a symmetry axis) may be dynamically stable. The mild instability due to the associated perturbation of the gravitational energy can be neutralized by the Coriolis forces induced by a slow rotation of the stellar core. The possible significance of magnetic cores for solar-type stars is discussed. Title: The big bang cosmology - enigmas and nostrums. Authors: Dicke, R. H.; Peebles, P. J. E. Bibcode: 1979grec.conf..504D Altcode: No abstract at ADS Title: Is there a chronometer hidden deep in the Sun? Authors: Dicke, R. H. Bibcode: 1978Natur.276..676D Altcode: No support is found for the conventional view of the sunspot cycle, that there exists a large random walk in the phase of the cycle. Instead, both sunspots and the [D/H] solar/terrestrial weather indicator seem to be paced by an accurate clock inside the Sun. Title: Operator Algebra and the Stationary States of Stellar Magnetic Fields (Paper dedicated to Professor Hannes Alfvén on the occasion of his 70th birthday, 30 May 1978) Authors: Dicke, R. H. Bibcode: 1978Ap&SS..55..275D Altcode: A vector-operator algebra technique for solving magnetic field problems in a toroidal/poloidal representation is illustrated with physical examples. Among the illustrative examples are calculations of necessary and/or sufficient conditions for the existence of stationary magnetic fields in stellar interiors. Title: Radiative equilibrium in the photosphere and global oscillations of the sun and an upper bound on energy transport. Authors: Dicke, R. H. Bibcode: 1978MNRAS.182..303D Altcode: Summary. The effect of non-local radiation equilibrium in the photosphere acting as a constraint on global oscillations (w 0.02, 1 < 3) is determined. It is shown that for a correctly chosen effective specific heat ratio the wave equation is very nearly adiabatic in form. The theory is used to compute upper bounds on energy transport to the upper atmosphere using the Grec- Fossat observations. These upper bounds are 3 5 orders of magnitude too small to be significant for the 1966 oblateness observations. Title: The Enigmatic Solar Distortion and the Solar Neutrino Problem Authors: Dicke, R. H. Bibcode: 1978sfsn.conf..109D Altcode: No abstract at ADS Title: The 12.2 day solar rotational period. Authors: Dicke, R. H. Bibcode: 1977ApJ...218..547D Altcode: The periodicity of the 1966 solar oblateness residuals, representing most of the variance, has been accounted for as a signal generated by a solar distortion rotating rigidly with a 12.22 + or - 0.12 day period (sidereal). It is shown that the complex noiselike character of the curve for residual variance versus frequency (including the numerous secondary resonances) is to be expected and represents the true 'fingerprint' of the 12.2-day distortion signal. Title: New Solar Rotational Period, the Solar Oblateness, and Solar Faculae Authors: Dicke, R. H. Bibcode: 1976PhRvL..37.1240D Altcode: The "excess" solar oblateness in 1966 and the periodicity in the residuals (most of the variance) can be described as a signal due to an approximately ellipsoidal sun rotating with a 12.2-day period, the major axis being tilted 85° +/- 1° from the solar axis. This result, independent of physical interpretation, precludes an explanation for the solar oblateness as a "brightness signal" due to the appearance of facular clusters at the solar limb. Title: Evidence for a solar distortion rotating with a period of 12.2 days. Authors: Dicke, R. H. Bibcode: 1976SoPh...47..475D Altcode: Most of the day-to-day fluctuation (originally believed to be error) in the Princeton solar oblateness observations is well described as the signal due to a ∼10 km distortion of the solar photosphere rotating rigidly with a period of 12.22±0.12 days (sidereal). This `solar-rotator' signal is well-defined by the observations and seems clearly significant statistically. Owing to the apparent precession of the solar spin-axis on the sky, the signal is not strictly periodic and has a wave-form that evolves with time in a predictable way. The previously discussed enigmatic periodicity of the oblateness residuals, for which no non-solar sources were found, is eliminated when the solar-rotator signal is subtracted. The residual errors are then found to be normally distributed and uncorrelated. Including the solar-rotator signal in the least-square fit increases the implied static oblateness by 16% to Δr = 45.8±3.3 millisec (equatorial excess radius). Both the static oblateness signal and the solar-rotator signal might be interpreted phenomenonologically as `brightness' signals due to a rigidly rotating non-uniform distribution of temperature in the upper photosphere. However, such a description encounters physical difficulties when the requirements of energy and momentum balance are considered. Including the excess static oblateness yields a distortion in the form of an ellipoid whose major axis is tilted 85° from the solar axis. Possible conflicts with other recent observations are discussed. Title: New Test of the Equivalence Principle from Lunar Laser Ranging Authors: Williams, J. G.; Dicke, R. H.; Bender, P. L.; Alley, C. O.; Carter, W. E.; Currie, D. G.; Eckhardt, D. H.; Faller, J. E.; Kaula, W. M.; Mulholland, J. D.; Plotkin, H. H.; Poultney, S. K.; Shelus, P. J.; Silverberg, E. C.; Sinclair, W. S.; Slade, M. A.; Wilkinson, D. T. Bibcode: 1976PhRvL..36..551W Altcode: An analysis of six years of lunar-laser-ranging data gives a zero amplitude for the Nordtvedt term in the Earth-Moon distance yielding the Nordtvedt parameter η=0.00+/-0.03 Thus, Earth's gravitational self-energy contributes equally, +/-3%, to its inertial mass and passive gravitational mass. At the 70% confidence level this result is only consistent with the Brans-Dicke theory for ω>29. We obtain |β-1|<~0.02 to 0.05 for five-parameter parametrized post-Newtonian theories of gravitation with energy-momentum conservation, or |β-1|<~0.01 if only β and γ are considered. Title: Phase-contrast detection of telescope seeing errors and their correction. Authors: Dicke, R. H. Bibcode: 1975ApJ...198..605D Altcode: The technique of phase-contrast microscopy applied to a telescope permits the detection and correction of phase errors in real time. These corrections can be made separately for two or more levels of the atmosphere. It may be possible to correct the seeing errors in a circular patch up to 2 min in diameter about a reference star with an apparent magnitude of 11 or brighter. Title: Real-time correction of telescope "seeing". Authors: Dicke, R. H. Bibcode: 1975JOSA...65.1206D Altcode: 1975OSAJ...65.1206D No abstract at ADS Title: Achromatic double-star interferometry. Authors: Wickes, W. C.; Dicke, R. H. Bibcode: 1974AJ.....79.1433W Altcode: No abstract at ADS Title: Research on solar physics, pulsars, and cosmology Authors: Dicke, R. H. Bibcode: 1974prnc.rept.....D Altcode: The contract was concerned with solar physics problems involving the solar oblateness, the precision timing of optical pulses from the crab nebula pulsar and the polarization and isotropy of the cosmic microwave background radiation. Title: The Enigmatic Periodicity of the Solar Oblateness Authors: Dicke, R. H. Bibcode: 1974SoPh...37..271D Altcode: The complex wave-form of the 25 2/3 day periodicity of the solar oblateness is exhibited. The statistical significance and strength of the fluctuation is examined. Using several lines of evidence the periodic fluctuation is shown to be a fluctuation in shape, not brightness. The fluctuation does not correlate with indicators of sunspots, faculae, prominences or magnetic fields. The detailed results of the analysis of the correlation with faculae are given. A possible explanation for the absence of the negative-correlated fluctuation delayed by 1/2 the period is examined. Title: Faculae and the Solar Oblateness. II Authors: Dicke, R. H. Bibcode: 1974ApJ...190..187D Altcode: Chapman and Ingersoll have suggested that the presence of a normally distributed error in their facular function may require a large increase in the estimate of the photospheric facular contribution to the solar oblateness signal. This effect is evaluated by using the Chapman-Ingersoll statistical assumptions and additional facular data from earlier studies. With the further assumption that there is no common systematic bias between the two facular signals, the above effect is found to be negligible, representing an additional 2-3 percent correction to the oblateness signal. The effects of systematic biases of the facular data are also examined. Subject headings: faculae, solar - gravitation - rotation, solar Title: The Oblateness of the Sun and Relativity Authors: Dicke, R. H. Bibcode: 1974Sci...184..419D Altcode: No abstract at ADS Title: The Oblateness of the Sun Authors: Dicke, R. H.; Goldenberg, H. Mark Bibcode: 1974ApJS...27..131D Altcode: The solar oblateness observations of 1966 are analyzed. Included are measures of the vertical and diagonal components of the oblateness. These components represent the fractional contractions of the solar disk along the north-south and the northeast-southwest diameters, respectively. Also included are the annular-ring measures of the equatorial brightening of the solar disk. These "brightness data" are obtained by scanning a thin annular aperture centered on the solar disk. The daily values of the diagonal component of the oblateness are correlated with the observatory temperature and humidity and with atmospheric transparency to test for a correlated atmospheric bias of the results. Seasonal averages of the hourly averages of the data provide measures of (and corrections for) the seeing distortions of the solar image. The correction of the diagonal component for seeing effects is zero. Functions derived from distributions about the limb of faculae, sunspots, magnetic fields, and prorninences are correlated with the diagonal component of the oblateness. Only the facular signal is important. The facular contribution is greatest when the largest amount of photosphere is exposed at the limb. Mter subtracting the facular contribution to the signal, the residual oblateness is independent of the amount of photosphere exposed. Averaged over all three limb exposures, only 14 percent of the oblateness signal is due to faculae. Correlation coefficients of the facular signal with the "brightness data" and with the vertical component of the oblateness are also computed. The "brightness data" show no equatorial brightening over and above that due to faculae. The 23d.67 periodicity of the solar oblateness is studied. The periodic autocorrelation function of the oblateness fluctuation, the periodic fluctuation component in the data, and the cross-correlation function of the data with the periodic component are evaluated. The periodic fluctuation component exhibits sharp positive peaks separated by 12 days. The values for the oblateness obtained from the diagonal and vertical components are consistent with each other and yield a mean value of ArIr = 4.31 + 0.34 x 10- . The solar quadrupole moment consistent with this value, j = 2.47 + 0.23 x 10 - 5, implies a correction of 2 .98 + per century to the `classical excess motion of Mercury's perihelion. Subject headings: faculae, solar - interiors, solar - Mercury - rotation, solar Title: Relativity and the solar oblateness Authors: Dicke, R. H. Bibcode: 1974exgr.conf..200D Altcode: No abstract at ADS Title: The Lunar Laser Ranging Experiment Authors: Bender, P. L.; Currie, D. G.; Dicke, R. H.; Eckhardt, D. H.; Faller, J. E.; Kaula, W. M.; Mulholland, J. D.; Plotkin, H. H.; Poultney, S. K.; Silverberg, E. C.; Wilkinson, D. T.; Williams, J. G.; Alley, C. O. Bibcode: 1973Sci...182..229B Altcode: No abstract at ADS Title: An automatic interferometer for double star observation Authors: Wickes, William C.; Dicke, R. H. Bibcode: 1973AJ.....78..757W Altcode: An interferometric device designed for measurement of the separation and position angle of double stars with separation less than 1 arcsec and large magnitude difference has been constructed. The instrument employs high-frequency photoelectric fringe detection, and signal averaging techniques to average atmospheric seeing effects. As part of the averaging process, the star field is rotated relative to the twin entrance apertures at a rate of 1 rps by means of a rotating dove prism. We report the results of measurements of double stars of small magnitude difference, carried out on several telescopes, a refractor, and reflectors. The measurements have accuracies better than 0-"01 in separation and 1' in position angle. Title: Solar Oblateness and Equatorial Brightening Authors: Dicke, R. H. Bibcode: 1973ApJ...180..293D Altcode: Equatorial brightening near the limb associated with an elevated temperature in the upper photosphere is discussed. It is not possible to obtain satisfactory agreement with the observations simultaneously at both of the color bands employed for the observations. The energy requirements of such hypothetical excess photospheric temperatures are severe, and the stresses needed for a force balance do not seem to be present. Subject headings: atmospheres, solar - gravitation - Sun Title: Photospheric Faculae and the Solar Oblateness Authors: Dicke, R. H. Bibcode: 1973NYASA.224..316D Altcode: No abstract at ADS Title: A self-consistent set of surface coordinates for the Apollo lunar laser retroreflectors deduced from laser range measures. Authors: Mulholland, J. D.; Plotkin, H. H.; Silverberg, E. C.; Wilkinson, D. T.; Alley, C. O.; Bender, P. L.; Currie, D. G.; Dicke, R. H.; Faller, J. E.; Kaula, W. M.; Williams, J. G. Bibcode: 1973spre.conf.1009M Altcode: 1973spre....2.1009M No abstract at ADS Title: A New Solar Fluctuation Authors: Dicke, R. H. Bibcode: 1972ApJ...176..479D Altcode: The fluctuation in the solar-oblateness signal during 1966 has been found to be strongly autocorrelated with a 25.3-day lag. The autocovariance functions show that the disturbed regions of the Sun occur in the vicinity of +45 latitude for which the synodic rotation period is 29.5 days. The 25-day correlation peak is positive as expected, but there is no indication of the equally strong 13-day negative halfrotation peak that would also be expected. It is concluded that the 25-day correlation may be due to density fluctuations occurring near the top of the radiative zone. Title: Faculae and the Solar Oblateness Authors: Dicke, R. H. Bibcode: 1972ApJ...175..831D Altcode: Chapman and Ingersoll have suggested that the excess solar oblateness found by Dicke and Golden- berg is wholly or largely due to the presence of faculae near the solar limb. This contrasts with my earlier statement based on a statistical study that contributions from faculae are unimportant. A new statistical study based on Chapman and Ingersoll's own facular function supports my 1970 statement. Title: Rotation and Lithium Abundance in Solar-Type Stars Authors: Dicke, R. H. Bibcode: 1972ApJ...171..331D Altcode: The mild thermally driven turbulence associated with the Goldreich-Schubert-Fricke instability induces diffusive transport of angular momentum and lithium. The same diffusivity controls both processes. The slowing of rotation observed in young solar-type stars and the rate of loss of angular momentum from the Sun to the solar-wind can be quantitatively related to the loss of lithium (and of beryllium if the instability extends deep enough). It is concluded that the instability cannot extend much deeper than the onset of fast burning of 7Li. By contrast, the assumption that a mild thermally driven turbulence is terminated at the boundary of a rapidly rotating core, perhaps by a jump in mean molecular weight A 10- , is used to give a quantitative account of the depletion of 7Li in the Sun and solartype stars. Lithium-6 should be strongly depleted, but 9Be not at all. The requirements that for the Sun both the rotation and the 7Li abundance agree with the observations give for each possible choice of core radius a value for the solar-wind torque and a lower bound for the angular velocity of the core. Title: Gravitation and the universe. Authors: Dicke, R. H. Bibcode: 1972grun.book.....D Altcode: No abstract at ADS Title: Geodesy results obtainable with lunar retroreflectors. Authors: Faller, J. E.; Bender, P. L.; Alley, C. O.; Currie, D. G.; Dicke, R. H.; Kaula, W. M.; MacDonald, G. J. F.; Mulholland, J. D.; Plotkin, H. H.; Silverberg, E. C.; Wilkinson, D. T. Bibcode: 1972uasg.proc..261F Altcode: No abstract at ADS Title: Laser Ranging Retroreflector Authors: Faller, J. E.; Alley, C. O.; Bender, P. L.; Currie, D. G.; Dicke, R. H.; Kaula, W. M.; MacDonald, G. J. F.; Mulholland, J. D.; Plotkin, H. H.; Silverberg, E. C.; Wilkinson, D. T. Bibcode: 1972NASSP.289...14F Altcode: No abstract at ADS Title: Evidence for the Distribution of Angular Velocity Inside the Sun and Stars - Comments Authors: Kraft, R.; Dicke, R. H. Bibcode: 1972NASSP.308..290K Altcode: 1972sowi.conf..290K No abstract at ADS Title: Geodesy Results Obtainable with Lunar Retroreflectors Authors: Faller, J. E.; Bender, P. L.; Alley, C. O.; Currie, D. G.; Dicke, R. H.; Kaula, W. M.; MacDonald, G. J. F.; Mulholland, J. D.; Plotkin, H. H.; Silverberg, E. C.; Wilkinson, D. I. Bibcode: 1972GMS....15..261F Altcode: Retroreflector packages have been carried to the moon by the Apollo 11, Apollo 14, and Apollo 15 missions, as well as by Luna 17. Laser ranging from the earth onto these packages should eventually yield information on polar motions and crustal movements accurate to a few centimeters, and on UT1 to 100 μsec. Present (1971) error of the range measurements is 30 cm, but accuracy to 3 cm should be obtainable with improvements in methods and equipment. Title: Internal Rotation of the Sun Authors: Dicke, R. H. Bibcode: 1972NASSP.300...23D Altcode: 1972poss.conf...23D; 1972pss..conf...23D No abstract at ADS Title: Solar Oblateness and the Abundance of Lithium in the Sun Authors: Dicke, R. H. Bibcode: 1971PhRvL..27..210D Altcode: The Goldreich-Schubert thermally driven turbulence extending to the deep interiors of solar-type stars which exhibit rotational slowing is precluded by spectroscopic observations showing the presence of lithium and beryllium. These observations, similar observations of the sun, the solar-wind torque, and the solar oblateness are consistent with a model for which such a turbulence is terminated at the surface of a rapidly rotating core containing 95% of the star's mass. Title: Abstract for Second Annual Lunar Science Conference in Houston January 11-14, 1971: Lunar Laser Ranging Experiment: Current Results and Future Plans Authors: Alley, C. O.; Bender, P. L.; Currie, D. G. L.; Dicke, R. H.; Faller, J. E.; Kaula, W. M.; MacDonald, G. J. F.; Mulholland, J. D.; Plotkin, H. H.; Silverberg, E. C.; Wilkinson, D. T. Bibcode: 1971LPI.....2...18A Altcode: No abstract at ADS Title: Preliminary results of laser ranging to a reflector on the lunar surface. Authors: Mulholland, J. D.; Alley, C. O.; Bender, P. L.; Currie, D. G.; Dicke, R. H.; Faller, J. E.; Kaula, W. M.; MacDonald, G. J. F.; Plotkin, H. H.; Wilkinson, D. T. Bibcode: 1971spre.conf...97M Altcode: No abstract at ADS Title: Laser Ranging Retroreflector Authors: Faller, J. E.; Alley, C. O.; Bender, P. L.; Currie, D. G.; Dicke, R. H.; Kaula, W. M.; MacDonald, G. J. F.; Mulholland, J. D.; Plotkin, H. H.; Silverberg, E. C.; Wilkinson, D. T. Bibcode: 1971NASSP.272..215F Altcode: No abstract at ADS Title: Internal Rotation of the Sun Authors: Dicke, R. H. Bibcode: 1970pss..conf...25D Altcode: No abstract at ADS Title: The Rotation of the Sun (review Paper) Authors: Dicke, R. H. Bibcode: 1970stro.coll..289D Altcode: 1970IAUCo...4..289D No abstract at ADS Title: Why are Sunspots Dark and Faculae Bright? Authors: Dicke, R. H. Bibcode: 1970ApJ...159...25D Altcode: It is shown that the darkening or brightening of a disturbed spot on the Sun's surface is uniquely determined by the abnormal stress distribution in the "seen layers" of the spot. The magnetic and velocity fields are the sources of the anomalous stress. A crude sunspot model based on the general theory is shown to give results in satisfactory agreement with the observations. Title: Internal Rotation of the Sun Authors: Dicke, R. H. Bibcode: 1970ARA&A...8..297D Altcode: No abstract at ADS Title: Laser Ranging Retro-Reflector: Continuing Measurements and Expected Results: Authors: Alley, C. O.; Chang, R. F.; Currie, D. G.; Poultney, S. K.; Bender, P. L.; Dicke, R. H.; Wilkinson, D. T.; Faller, J. E.; Kaula, W. M.; MacDonald, G. J. F.; Mulholland, J. D.; Plotkin, H. H.; Carrion, W.; Wampler, E. J. Bibcode: 1970Sci...167..458A Altcode: After successful acquisition in August of reflected ruby laser pulses from the Apollo 11 laser ranging retro-reflector (LRRR) with the telescopes at the Lick and McDonald observatories, repeated measurements of the round-trip travel time of light have been made from the McDonald Observatory in September with an equivalent range precision of ± 2.5 meters. These acquisition period observations demonstrated the performance of the LRRR through lunar night and during sunlit conditions on the moon. Instrumentation activated at the McDonald Observatory in October has yielded a precision of ± 0.3 meter, and improvement to ± 0.15 meter is expected shortly. Continued monitoring of the changes in the earth-moon distance as measured by the round-trip travel time of light from suitably distributed earth stations is expected to contribute to our knowledge of the earth-moon system. Title: The Solar Oblateness and the Gravitational Quadrupole Moment Authors: Dicke, R. H. Bibcode: 1970ApJ...159....1D Altcode: The connection between the oblateness and the gravitational quadrupole moment of the Sun is developed under the assumption of the absence of magnetic and velocity fields in the surface layers. This discussion is generalized to include also the effects of surface rotation for rotation on cylinders. The theory of the generation by surface fields of oblateness and equatorial temperature excess is developed and used to discuss the various attempts by Roxburgh, Cocke, Sturrock, and Gilvarry to account for the observed oblateness as an effect of surface fields only. The severe constraint on allowed surface fields introduced by the observed latitude independence of solar brightness is analyzed. It is concluded that an acceptable explanation of the solar oblateness, other than the effects of a gravitational quadrupole and surface rotation, has yet to be found. Title: Laser-ranging retro-reflector: continuing measurements and expected results Authors: Alley, C. O.; Chang, R. F.; Currie, D. G.; Poultney, S. K.; Bender, P. L.; Dicke, R. H.; Wilkinson, D. T.; Faller, J. E.; Kaula, W. M.; MacDonald, G. J. F.; Mulholland, J. D.; Plotkin, H. H.; Carrion, W.; Wampler, E. J. Bibcode: 1970GeCAS...1.1947A Altcode: 1970LPSC....1.1947A No abstract at ADS Title: Gravitation and the universe Authors: Dicke, Robert H. Bibcode: 1970grun.conf.....D Altcode: No abstract at ADS Title: Average acceleration of the earth's rotation and the viscosity of the deep mantle. Authors: Dicke, R. H. Bibcode: 1969JGR....74.5895D Altcode: The acceleration of the earth's rotation averaged over the past 3000 years has been re-studied using a new analysis of the ancient eclipses. The relaxation time for a second-order harmonic distortion of the earth has been calculated to fall in the range 870-1600 years. This short relaxation time seems to require a viscosity for the deep mantle of ∼1022 poises, permitting the convective transport of heat from the deep interior of the earth. If the viscosity is this low, deep convective currents are required to support the excess equatorial bulge. Title: The Age of the Galaxy from the Decay of Uranium Authors: Dicke, R. H. Bibcode: 1969ApJ...155..123D Altcode: The dating of the Galaxy by the decay of uranium is re-examined. From recently published data it is concluded that the Galaxy is approximately 7 X 1O~ years old, substantially the same as the "prompt synthesis" age derived eleven years ago by Burbidge, Burbidge, Fowler, and Hoyle. Contrary to current beliefs, the results obtained from the decay of U235 relative to U238, assuming "prompt synthesis," are concordant with those based on the decay of U238 relative to Th2~2 Title: Some implications for physics and geophysics of laser range measurements from Earth to a lunar retro-reflector. Authors: Alley, C. O.; Bender, P. L.; Currie, D. G.; Dicke, R. H.; Faller, J. E. Bibcode: 1969ampe.conf..523A Altcode: No abstract at ADS Title: The Equivalence of Inertial and Gravitational Mass Authors: Dicke, R. H. Bibcode: 1969tsra.conf..375D Altcode: 1969qhea.conf..375D No abstract at ADS Title: Gravitation and the universe. Authors: Dicke, R. H. Bibcode: 1969grun.book.....D Altcode: No abstract at ADS Title: Laser Ranging Retroreflector Authors: Alley, C. O.; Bender, P. L.; Chang, R. F.; Currie, D. G.; Dicke, R. H.; Faller, J. E.; Kaula, W. M.; MacDonald, G. J. F.; Mulholland, J. D.; Plotkin, H. H.; Poultney, S. K.; Wilkinson, D. T.; Winer, Irvin; Carrion, Walter; Johnson, Tom; Spadin, Paul; Robinson, Lloyd; Wampler, E. Joseph; Wieber, Donald; Silverberg, E.; Steggerda, C.; Mullendore, J.; Rayner, J.; Williams, W.; Warner, Brian; Richardson, Harvey; Bopp, B. Bibcode: 1969NASSP.214..163A Altcode: No abstract at ADS Title: The variability of atomic constants. Authors: Dicke, R. H. Bibcode: 1969atph.conf..103D Altcode: 1969agph.conf..103D No abstract at ADS Title: Remarks on gravitation and cosmology Authors: Dicke, R. H. Bibcode: 1969cp1..conf..507D Altcode: No abstract at ADS Title: Eine neue Gravitationstheorie. Authors: Dicke, R. H. Bibcode: 1969Umsch..69..665D Altcode: No abstract at ADS Title: Origin of the Globular Star Clusters Authors: Peebles, P. J. E.; Dicke, R. H. Bibcode: 1968ApJ...154..891P Altcode: We argue that the globular clusters may have originated as gravitationally bound gas clouds before the galaxies formed. This idea follows from the primeval-fireball picture, which suggests that the first bound systems to have formed in the expanding Universe were gas clouds with mass and shape quite similar to the globular star clusters. We present also a picture for the evolution from these assumed proto- globular gas clouds to globular star cluster Title: Scatter-Hole Cameras for X-Rays and Gamma Rays Authors: Dicke, R. H. Bibcode: 1968ApJ...153L.101D Altcode: A pinhole camera for which the entrance area, covered with a very large number of randomly dis- tributed pinholes, is 50 per cent open is shown to be a very effective way of forming images of a complex of X-ray stars. A simple statistical trick is used to reduce the multitudinous overlapping images to a single image. Less than forty detected photons are needed to form an image of a single star Title: Scalar-Tensor Gravitation and the Cosmic Fireball Authors: Dicke, R. H. Bibcode: 1968ApJ...152....1D Altcode: It has been shown that under conventional general relativity the cosmic fireball should convert 26- 28 per cent of the hydrogen to helium. Departure from an ideal isotropic and uniform universe should only increase the amount of helium formation. The contribution from the scalar field energy of the scalar- tensor type of gravitation theory can lead to the fireball's expanding so rapidly that virtually no helium is formed. If the present mass density of the Universe is in excess of 2 X 10-29 g cm3, corresponding to a closed space, zero helium production would be expected under the scalar-tensor theory. Thus a de- termination of the helium content of Population II stars could provide a test for both theories of gravita- tion. INTRODUCTIO Title: Solar Oblateness and Fluid Spin-Down Authors: McDonald, B. E.; Dicke, R. H. Bibcode: 1967Sci...158.1562M Altcode: An experiment performed on a differentially rotating, density-stratified fluid shows that "spin-down" need not occur under the condition of stratification. Inasmuch as density stratification occurs in the interior of the sun, spin-down probably does not exist in the solar interior, and the observed solar oblateness may indicate that the sun contains a rapidly spinning core. Title: The Solar Spin-Down Problem Authors: Dicke, R. H. Bibcode: 1967ApJ...149L.121D Altcode: No abstract at ADS Title: Solar Models Authors: Dicke, R. H. Bibcode: 1967Sci...157..960D Altcode: No abstract at ADS Title: Differential Rotation and the Solar Oblateness Authors: Dicke, R. H.; Goldenberg, H. Mark Bibcode: 1967Natur.214.1294D Altcode: A few weeks ago, Dr I. W. Roxburgh questioned an earlier argument by Professor R. H. Dicke that the observed flattening of the Sun would account for part of the rotation of the orbit of Mercury otherwise attributable to general relativity. Roxburgh advanced arguments which suggest that the surface of the Sun may not be an equipotential surface, largely because of turbulence in the atmosphere. Dicke now rejects this interpretation. Title: Solar Oblateness-A Letter Authors: Dicke, R. H. Bibcode: 1967IrAJ....8...63D Altcode: No abstract at ADS Title: Cosmological Enigmas. (Book Reviews: Worlds-Antiworlds. Antimatter in Cosmology) Authors: Dicke, R. H. Bibcode: 1967Sci...155.1527D Altcode: 1967Sci...155.1527A No abstract at ADS Title: Solar Oblateness and General Relativity Authors: Dicke, R. H.; Goldenberg, H. Mark Bibcode: 1967PhRvL..18..313D Altcode: New measurements of the solar oblateness have given a value for the fractional difference of equatorial and polar radii of (5.0+/-0.7)×10-5. A corresponding discrepancy of 8% of the Einstein value for the perihelion motion of Mercury is implied. Title: Gravitation Authors: Dicke, Robert H. Bibcode: 1967easp.book..264D Altcode: No abstract at ADS Title: The Secular Acceleration of the Earth's Rotation and Cosmology Authors: Dicke, R. H. Bibcode: 1966ems..conf...98D Altcode: No abstract at ADS Title: Stellar Evolution with Varying G Authors: Dicke, R. H. Bibcode: 1966stev.conf..319D Altcode: No abstract at ADS Title: Astrophysics and Radio Astronomy. (Book Reviews: General Relativity and Cosmology) Authors: Dicke, R. H. Bibcode: 1965Sci...149.1493M Altcode: No abstract at ADS Title: Icarus and relativity Authors: Dicke, R. H. Bibcode: 1965AJ.....70..395D Altcode: The regression of the node of Icarus is proposed as a sensitive measure of the oblateness of the sun. Title: Cosmic Black-Body Radiation. Authors: Dicke, R. H.; Peebles, P. J. E.; Roll, P. G.; Wilkinson, D. T. Bibcode: 1965ApJ...142..414D Altcode: No abstract at ADS Title: Gravitation and Space Science Authors: Dicke, R. H.; Peebles, P. J. Bibcode: 1965SSRv....4..419D Altcode: No abstract at ADS Title: Optical Radar Using a Corner Reflector on the Moon Authors: Alley, C. O.; Bender, P. L.; Dicke, R. H.; Faller, J. E.; Franken, P. A.; Plotkin, H. H.; Wilkinson, D. T. Bibcode: 1965JGR....70.2267A Altcode: In a recent letter Hunt [1964] described a microwave transponder that can be landed on the moon and that can be used, in conjunction with a modified Glotrac station, to measure the distance between station and landing site. He also suggests several interesting measurements that could be made on the earth-moon system if the range accuracy were sufficiently well developed. The purpose of this letter is to point out the capabilities and possible advantages of an optical radar system which uses a corner reflector on the moon's surface. Smullin and Fiocco [1962] have demonstrated that laser beams can be scattered from the moon's surface and detected back at the earth; however, the return signals were too weak and too spread out (in time) to be used for precision ranging. Hoffman et al. [1960] have pointed out the advantages of using corner reflectors on an artificial satellite to permit precision tracking. More recently, Plotkin [1964] has described an optical radar system that is capable of making precision range measurements to satellites which have been equipped with corner reflectors. Title: Cosmology and Newtonian Mechanics Authors: Callan, C.; Dicke, R. H.; Peebles, P. J. E. Bibcode: 1965AmJPh..33..105C Altcode: The general relativistic solution to the cosmological problem is often considered to be one of its most beautiful results. It is shown that Newtonian mechanics is quite sufficient to discuss the dynamics of the expanding universe. Furthermore, this is not a cleverly contrived classical model, or a crude nonrelativistic approximation, but a completely correct discussion of the dynamics of the expansion in a region where both general relativity and Newtonian mechanics are equally valid. Title: The Sun's Rotation and Relativity Authors: Dicke, R. H. Bibcode: 1964Natur.202..432D Altcode: No abstract at ADS Title: Evolution of the Solar System and the Expansion of the Universe Authors: Dicke, R. H.; Peebles, P. J. Bibcode: 1964PhRvL..12..435D Altcode: No abstract at ADS Title: Cosmology, Mach's Principle and Relativity Authors: Dicke, R. H. Bibcode: 1963AmJPh..31..500D Altcode: The significance of Mach's principle (and the implicit relativity principle) for field theory is discussed, also the significance of zero-mass boson fields for the geometry of the physical space. The significance of such fields for Mach's principle within the framework of cosmology is also discussed. It is suggested that the distant matter of the universe generates one or two zero-mass boson fields, very likely a tensor field and perhaps a scalar, and that each of these fields propagates, carrying into the laboratory a quasistatic influence having its origin primarily in the distant matter of the universe. The observable effects of these ``Machian fields'' are described. Title: Cosmology and the Radioactive Decay Ages of Terrestrial Rocks and Meteorites Authors: Peebles, P. J.; Dicke, R. H. Bibcode: 1962PhRv..128.2006P Altcode: Several different cosmologies have been proposed in which the strength of the gravitational interaction is variable. Also, it has been suggested that the gravitational interaction may play a significant role in determining the structure of elementary particles, and in particular that the value of the fine structure constant may depend on the strength of the gravitational interaction. It is shown that these two effects taken together would lead to observable discrepancies in the ages of terrestrial rocks and meterorites as determined by different radioactive decay schemes. Analysis of the geophysical data leads to an upper limit of about 3 parts in 1013 per year on the rate of change of the fine structure constant. If the assumed relation between gravitation and particle structure were valid, this would correspond to a limit on variations in the strength of the gravitational interaction of 2 parts in 1011 per year. This upper limit is one-fifth of the size of the variations expected according to Dirac's cosmology, and roughly as big as the variation to be expected according to the Brans-Dicke cosmology. It is concluded that either the assumed connection between gravitation and elementary particles does not exist, or, if the connection does exist, that the geophysical data provide a significant limit on possible variations in the strength of the gravitational interaction. Title: The Earth and Cosmology Authors: Dicke, R. H. Bibcode: 1962Sci...138..653D Altcode: No abstract at ADS Title: The Temperature of Meteorites and Dirac's Cosmology and Mach's Principle Authors: Peebles, J.; Dicke, R. H. Bibcode: 1962JGR....67.4063P Altcode: Arguments based on Mach's principle and on numerical coincidences in the astrophysical data lead to the idea that the strength of the gravitational interaction may be decreasing with time. This would imply that the radiation rate of the sun was larger in the past and that asteroids and meteorite bodies were warmer, possibly leading to loss of argon from the material of the meteorites. It is shown from the observed potassium-argon ages of meteorites that the strength of the gravitational interaction has not been decreasing by more than about 1 part in 1010 per year. This limit does not seem to rule out any of the cosmologies in which the strength of the gravitational interaction is variable. Title: Significance of Spatial Isotropy Authors: Peebles, P. J.; Dicke, R. H. Bibcode: 1962PhRv..127..629P Altcode: It has been suggested occasionally that the fine structure "constant" may not be a fixed number, but that it may be determined, in a manner not yet understood, by the distribution of mass in the universe. A simple point-particle picture is used to indicate the significance of this idea for the motion of free test particles. The possible generally covariant equations of motion for a point particle are considered, and it is shown that one can find a suitable model which is consistent with the observed structure independence of gravitational acceleration. However, it is indicated that such a model is not consistent with the precise observations, made by Hughes et al. and Drever, of the local isotropy of space. That is, with the observed structure independence of gravitational acceleration and local isotropy of space, and assuming general covariance, it seems to be necessary to rule out any appreciable variation with position in the value of the fine structure constant. Title: Long-Range Scalar Interaction Authors: Dicke, R. H. Bibcode: 1962PhRv..126.1875D Altcode: The long-range scalar field, associated with a neutral, massless, boson, has been generally considered to be nonexistent. This belief is based on the lack of overt effects, observed in the laboratory, from such a field. It is shown that if this long-range interaction were to exist, it would of necessity be weak. The physical reason for this is the large contribution, having its origin in the enormous amount of matter at great distance in the universe, to the magnitude of the scalar. By comparison, the contribution of local matter is miniscule, leading to a weak interaction of about the same strength as gravitation. Furthermore, it is shown that such an interaction, in its effects, would be very similar to gravitation and could be distinguished only with difficulty. It is concluded that there is not yet a compelling observation which could be used to exclude the long-range scalar interaction. Title: Lee-Yang Vector Field and Isotropy of the Universe Authors: Dicke, R. H. Bibcode: 1962PhRv..126.1580D Altcode: Lee and Yang suggested that, associated with heavy-particle conservation, there may exist an analog of the electromagnetic field, a field for which nucleons and antinucleons would serve as positive and negative "charges." It is shown that the null result from a recent repetition of the Eötvös experiment implies that, if it exists, the Lee-Yang interaction is at most only 10-7 of the gravitational interaction. This great weakness does not imply that the field does not exist. However, with the assumption of the isotropy of the average matter distribution of the universe, the Lee-Yang antisymmetric field tensor vanishes when averaged over sufficiently large volumes. This implies that, if the Lee-Yang field exists, nucleons and antinucleons are present in equal numbers in the universe, presumably gathered in matter and antimatter galaxies. However, it is found that the fact that a copious stream of γ rays is not present in the cosmic rays can be used to exclude such numbers of antimatter galaxies. It is concluded that the Lee-Yang field probably does not exist. Title: Dating the Galaxy by Uranium Decay Authors: Dicke, R. H. Bibcode: 1962Natur.194..329D Altcode: No abstract at ADS Title: Implications for Cosmology of Stellar and Galactic Evolution Rates Authors: Dicke, R. H. Bibcode: 1962RvMP...34..110D Altcode: No abstract at ADS Title: Periodicity of Earthquakes and the Invariance of the Gravitational Constant Authors: Morgan, W. J.; Stoner, J. O.; Dicke, R. H. Bibcode: 1961JGR....66.3831M Altcode: Times of occurrence for a total of 1933 earthquakes are analyzed for periodicities. The results show no definite evidence for effects due to earth tides. Small indications of a solar-date periodicity are assumed to be thermal in origin. A strong, statistically significant annual period is found, and the phase is substantially the same for northern and southern earthquakes. This periodicity is not wholly accounted for by temperature effects, wind-induced stresses, and observer bias. The occurrence of this periodicity would be understandable if the gravitational constant were to vary as the earth-sun distance changes or as the earth's velocity relative to a preferred coordinate frame changes; however, the observed periodicity cannot be interpreted as conclusive support for such a hypothesis. Title: Dirac's Cosmology and Mach's Principle Authors: Dicke, R. H. Bibcode: 1961Natur.192..440D Altcode: THE dimensionless gravitational coupling constant with mp the mass of some elementary particle, for definiteness taken as the proton, is such a small number that its significance has long been questioned. Thus Eddington1 considered that all the dimensionless physical constants, including this one, could be evaluated as simple mathematical expressions. Dirac2 considered that such an odd number must be related to other numbers of similar size, characterizing the structure of the universe. However, most physicists seem to believe that a dimensionless constant, such as (1), is provided by Nature, cannot be calculated, and is not in any way related to other numbers. Title: On the Spring Maximum of Radioactive Fallout from Nuclear Test Explosions Authors: Bleichrodt, J. F.; Blok, Joh.; Dicke, R. H. Bibcode: 1961JGR....66..135B Altcode: Some results of measurements are presented pertaining to the maximum of fallout which was observed during the spring of the last few years. Evidence is presented that the height of this maximum is chiefly determined by the amount of radioactive debris present in the temperate or polar lower stratosphere, whereas seasonal factors determine the time of appearance of the maximum. Title: The Nature of Gravitation Authors: Dicke, R. H. Bibcode: 1961sis..book...91D Altcode: No abstract at ADS Title: Tracking and Orbit Requirements for Experiment to detect Variations in Gravitational Constant Authors: Dicke, R. H.; Hoffmann, W. F.; Krotkov, R. Bibcode: 1961spre.conf..287D Altcode: No abstract at ADS Title: Mach's principle and equivalence Authors: Dicke, R. H. Bibcode: 1961egt..conf....1D Altcode: No abstract at ADS Title: Comparison between theory and observation for the outer planets Authors: Krotkov, R.; Dicke, R. H. Bibcode: 1959AJ.....64..157K Altcode: - bstract. The auto-covariance function of the differences between the observed and predicted ecliptic longitudes of Jupiter indicates that these residuals contain a trigonometric term of period 4520 days, compared with 4333 days for Jupiter's period, and amplitu e d'. .No currently known source of systematic error would account for such a period. The residuals for the other outer p Thets contain no period as marked as the 4520 day period in Jupiter. A secular increase in the eccentricity of 1/3 X 10-6 per century, together with a motion of the perihelion in the direction of Jupiter's revo- lution about the sun and amounting to 5" per century will, coupled with a term whose frequency is equal to Jupiter's mean motion, produce such a period. If such secular perturbations were produced by a constant anomalous acceleration of Jupiter, the magnitude of the acceleration required would be about times the Jovian centripetal acceleration. The data for the other outer planets are inadequate to either confirm or deny the existence of such an acceleration in their motion. Title: Dirac's Cosmology and the Dating of Meteorites Authors: Dicke, R. H. Bibcode: 1959Natur.183..170D Altcode: IT was long ago suggested by Dirac1 that, from considerations based upon the sizes of the important physical and astrophysical constants, there were reasons for believing that the gravitational constant, when expressed in atomic units, was not a true constant but that it varied inversely with the age of the universe. It has been pointed out that of the other physical constants, only the weak coupling constant would be expected to vary strongly with time, assuming the correctness of the Dirac hypothesis2. Title: Microwave Radiation from the Sun and Moon. Authors: Dicke, Robert H.; Beringer, Robert Bibcode: 1946ApJ...103..375D Altcode: No abstract at ADS Title: The radial distribution in globular clusters Authors: Dicke, Robert H. Bibcode: 1939AJ.....48..108D Altcode: No abstract at ADS