Roberto Martins Searching for the Ether DIO 17
Much later, Courvoisier presented another confirmation of this effect. He compared the catalogues of time correction of the observatories of Greenwich, Potsdam, Buenos Aires and Mount Stromslo for the period from 1948 to 19 54.28 There was a nice agreement between the theoretical predictions and the observed time differences, especially in the case of the years 1951-1954.
Local comparison between pendulum clock and chronometer Courvoisier supposed that the rate of pendulum clocks would vary because of the periodical gravity changes, but mechanical chronometers should not suffer similar changes. Therefore it should be possible to observe effects due to the absolute motion of the Earth comparing pendulum clocks to mechanical chronometers at a single place. Comparisons were made both at Babelsberg and at Potsdam (with the help of Wanach). In his analysis, Courvoisier assumed the value D = +40° and obtained^ = 104° ± 9° and v = 750 km/s.
Gravimetric observations
If the Lorentz contraction of the Earth produces gravitational effects, then it should be possible to find its influence on the tides. Esclangon analyzed a set of 166,500 tide measurements, made at Pola, on the Adriatic sea, from 1898 to 1916. He obtained a term with the period of on sidereal day, that could not be associated with the Sun or the Moon, and ascribed it to a “dissymmetry of space”.29 This tidal effect could be described as:
48 mm.cos (t -146.1°) + 25 mm.cos (t - 244.6°) (16)
If the local gravity undergoes periodic changes, it should be possible to detect this effect with sensitive gravimeters. In 1927 Courvoisier (with the help of Sergei Gaposchkin) attempted for the first time to measure gravity variations using a very sensitive torsion gravimeter.30 The instrument could
detect a change Ag/g of 3xl0-^, corresponding to a displacement of 0.2 mm of the gravimeter pointer. From a series of measurements undertaken from 1927 to 1928 Courvoisier computed the following values:
A = 62° ± 5°; D = +32° ± 8°; v = 543 ± 55 km/s
28 Leopold Courvoisier, “Der Einfluss der ‘Lorentz-Kontraktion’ der Erde auf den Gang der Quarzuhren”, Experientia, ix (1953), 286-7; xiii (1957), 234-5.
29 Ernest Esclangon, “La dissymétrie de l'espace sidéral et le phénomène des marées”, Comptes rendus de l’académie des sciences de Paris, clxxxiii (1926), 116-18.
30 Leopold Courvoisier, “Über die Translationsbewegung der Erde im Lichtäther”,
Physikalische Zeitschrift, xxviii (1927), 674-80.
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Roberto Martins
Searching for the Ether
DIO 17
In 1932 Courvoisier obtained new results, taking into account in this new paper some effects due to temperature and humidity. The new results obtained by him were
A = 50° ± 7°; D = +45° ± 18°; v = 498 ± 78 km/s
For the first time, Courvoisier's results were criticized and checked. In 1932, Rudolf Tomaschek and Walter Schaffernicht reported gravity measurements made with a new kind of gravimeter that was able to detect _0
changes Ag/g of 10 . The instrument was placed inside a cave in a mountain, where the temperature was constant to 0.001° C. No effect of the order of magnitude predicted by Courvoisier was observed.31
Eclipses of Jupiter’s satellites
It is well known that in 1879 James Clerk Maxwell wrote to David Peck Todd asking him about the possibility of computing the velocity of the solar system through the ether using available data on occultation of Jupiter’s satellites.32 Maxwell supposed that the motion of the solar system would produce an anisotropy of the speed of light that could be detected as a fluctuation of the times of occultation of Jupiter's satellites, observed from the Earth, with a period of about 12 years. Todd answered, however, that the measurements available at that time were not precise enough for such computations.
In 1930 Courvoisier published a paper where he presented an analysis of available observations of Jupiter's satellites and claimed that they led to a new determination of the velocity of the solar system relative to the ether.33 He used data relative to the three inner Galilean satellites published by the Johannesbourg observatory (1908-1926), comparing those measurements to those of the observatories of Cape Town, Greenwich and Leyden (1913-1924). He confirmed Maxwell's anticipation of a fluctuation with a period of about 12 years and obtained the following results:
A = 126° ± 10°; D = +20°; v = 885 ± 100 km/s Secular aberration of light
According to the theory of ether accepted by Courvoisier, the speed of light is constant relative to the ether, but could not be constant relative to the
31 Rudolf Tomaschek and Walter Schaffernicht, “Zu den gravimetrischen Bestimmungsversuchen der absoluten Erdbewegung”, Astronomische Nachrichten, ccxliv (1932), 257-66.
32 James Clerk Maxwell, “On a possible mode of detecting a motion of the solar system through the luminiferous ether”, Proceedings of the royal society ofLondon, xxx (1879-1880), 108-10.
33 Leopold Courvoisier, “Ableitung der ‘absoluten’ Erdbewegung aus beobachteten Längen der Jupiter-Satelliten”, Astronomische Nachrichten, ccxxxix (1930), 33-38.
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