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Dr. Chalmers W. Sherwin
local time: 2023-01-29 04:23 (-07:00 DST)
Dr. Chalmers W. Sherwin (Abstracts)
Titles Abstracts Details
  • Measurement of the One-Way Speed of Light (2002) [Updated 6 years ago]

    Using the Phipps protocol to establish the absolute phase (synchronism) of a remote clock, we conclude that a one-way measurement of the speed of light is possible. The analysis focuses on precisely-defined experimental operational procedures, and uses only technologically-feasible, automatic-recording instruments which operate independently of human observers. It is not based on the theory of relativity, but rather depends on one key experimentally-supported hypothesis: the frequency f of a clock moving with self-measured (proper) speed V in inertial frame S is f = f0 / Sqrt(1 + v2/c2), where f0 is the frequency of the clock when it is at rest in S, and c is the two-way speed of light. A preliminary survey of the frequency stability and synchronization procedures used in Very Long Base Line astronomical arrays and in the satellite-based Global Positioning System suggests that data already exist which demonstrate that the one-way speed of light deviates from the two-way speed by less than one part in 107, or about 30 m/sec.

    Published posthumously.

  • In Memory: Chalmers W. Sherwin (1998) [Updated 9 years ago]
    by Thomas E. Phipps, Chalmers W. Sherwin   read the paper:

  • An Analysis of the Silvertooth Experiment (1989) [Updated 6 years ago]

    An analysis is made of the experimental features of Silvertooth's experiment, which claims to detect an ether wind using counterpropagating optical beams. The author confirms Phipps's conclusion that the bright fringes (antinodes) that Silvertooth observes at the output of his photodetector cannot be affected by the phase of the light signal at the photocathode. In particular, an output fringe cannot have a negative value. Our analysis shows that Silvertooth's use of ac-coupling between his photodetector and the oscilloscope on which the fringe profiles are displayed will cause what are actually nulls (nodes) to appear on the display to be fringes of negative amplitude or ?inverse phase.? If he had used dc-coupling all the null regions would non-negative, and this confusion would not be possible. His observed effects attributed to the ether wind could be caused by a very small misalignment (of the order of 1/4) in a total traverse of his photodetector/mirror system of approximately 500.

  • New Experimental Test of Lorentz's Theory of Relativity (1987) [Updated 6 years ago]

    A new experimental test of H. A. Lorentz's [Theory of Electrons (Columbia University Press, New York, 1909)] theory of relativity exploits a neglected concept of Lorentz, that the physical contraction of macroscopic matter moving with a velocity v, with respect to a postulated preferred inertial frame S (the ether), is caused by the relativistic shortening of the equilibrium lengths of the low-mass electronic bonds in a direction parallel to v. Following a change in the orientation of the bond with respect to v, this contraction generates what we call a transient Lorentzian stress. In all prior experiments in which a macroscopic structure is rotated with respect to a hypothesized v, this stress is so rapidly relieved that the macroscopic length adiabatically follows the length demanded by the bonds and no experimental consequences are observable, even with v as great as 10-3c. In the new experiment, a structure of length L is rotated at an angular frequency WR about one end in a horizontal plane containing the postulated velocity v. At low rotation rates, when 2WR (the frequency of the transient Lorentzian stress) is small compared to Wv (the radial resonant vibration frequency of the rotating structure) both Einstein and Lorentz predict that its outer end should enscribe an exact circle, but, when 2wR approaches Wv (a requirement which causes very large stretching of the structure over its normal length) the Lorentz theory uniquely predicts that the transient stress does not have time to be fully relieved, and the outer end should enscribe an elliptical path which deviates from an exact circle by an amount ~ Lv2/c2, since the length of each atomic bond parallel to v changes by the factor (1- v2/c2)1/2. A null result was observed for the case where the postulated velocity v is that of the frame in which the cosmic background radiation is isotropic.

  • Electromagnetic Mass and the Inertial Properties of Nuclei (1960) [Updated 6 years ago]

    According to the theory of relativity the inertial mass of any physical system should be a scalar quantity (no matter how distorted its electromagnetic structure) and the 'excess' inertial mass of electromagnetic origin should not be observable. Experimental evidence on both these points was examined for nuclei. Nuclei are particularly significant for this test because they are the only structures (excepting the elementary particles) which possess an appreciable fraction of their net mass in the form of electrostatic energy, they are the only structures which are formed as a result of the equilibrium between two very different types of known forces (electromagnetic, and nuclear), and their dimensions are large enough that there is reason to trust the validity of the electromagnetic laws. It is found that the inertial mass of a distorted nucleus, as measured by a mass spectrometer, has no observable asymmetry to an accuracy of 1 part in 100 of the asymmetry which is calculated to exist as a consequence of the electromagnetic energy. It is found that a comparison of nuclear mass differences (as measured by the mass spectrometer and by nuclear reactions) shows that the 'excess' electromagnetic inertial mass is not observable, to an accuracy of 1 part in 600.

    Report I-92, 14 March, 1960, Coordinated Science Laboratory, University of Illinois, formerly available from U. S. Department of Commerce, Clearinghouse for Federal Scientific and Technical Information, document acquisition number AD0625706. This organization no longer exists under that name and the document is apparently no longer available at any price to the taxpayers who paid for the work. Further citation information. It is referenced in Phipps (1986), Van Flandern (1998), and Phipps (2009).

  • Some Recent Experimental Tests of the "Clock Paradox" (1960) [Updated 6 years ago]

    Recent experiments by Pound and Rebka on the temperature dependence of the M?ssbauer effect in Fe57, and by Hay, Schiffer, Cranshaw, and Egelstaff using an Fe57 absorber on a rotating drum are shown to provide the first direct experimental verification of the time-keeping properties of accelerated clocks such as occur in the classic "clock paradox" of relativity. In the experiment by Pound and Rebka, the thermal vibrations of the lattice impart rms velocities of about 10-6c, and nearly continuous, randomly-oriented accelerations of the order of 1016g to both the source and the absorber nuclei. In the experiment by Hay et al. the acceleration of the absorber was 6?104g. The photon provides continuous communication of time data between the two nuclei for the duration of the "journey" (the emission time of the quantum). In each case the observed fractional frequency shift Δf/f0 which occurs between the source and the absorber is found to be -vs2/2c2+va2/2c2, where vs and va are the rms velocities of the source and the absorber nuclei, respectively. These results are in quantitative agreement with the generally accepted calculations for the "clock paradox", in which two clocks pursue independent paths (at least one of which involves accelerations) in a common inertial frame, but are compared at two or more points where they coincide in space and time. The temperature-dependent experiments also demonstrate that accelerations of the order of 1016g, arising from lattice vibrations, produce no intrinsic frequency shift in Fe57 nuclei to an accuracy exceeding 1 part in 1013.