Pendulum "Sees" Eclipse

The Fundamental Problem With Clocks and the Definition of Time


In the age when the pendulum clock was the most exact timekeeping device, no one would have believed what present-day precise measurements revealed: That a pendulum shows a slight reaction when a solar eclipse occurs. I know of no scientific explanation for this phenomenon.

To make my point before I give the facts: In science, time is defined by clocks. And these clocks can be faulty. In hundred years our atomic clocks may seem archaic, even if viewed as the best solution currently possible. What we record as time may be regarded as poorly defined.

Even today, various definitions exist side by side. For example the tropical year is defined by some in terms of seconds measured by an array of atomic clocks, and by others as the time between two vernal equinoxes (see long article by Simon Cassidy ERROR in GRO #48) - in other words: direct observation. Occasional leap seconds "synchronize" the two definitions.

These and other more or less differing definitions of a unit of time will not concern the layman. But there may come a change in the definition of time, if similar quantum "effects" are discovered that challenge the assumptions atomic clocks are based on. And that may have technological consequences (among others).

I have not had the time to follow recent scientific literature in depth, so my views expressed here may be outdated. If you find related information, by Science Citation Index or otherwise, be it supportive or contradicting, please let me know.


In his book "The End of the Scientific Age", Herbert Pietschmann writes (translated from the German original: "Das Ende des naturwissenschaftlichen Zeitalters", ISBN 3 548 34148 9, Frankfurt/Main, Berlin 1983. Ellipsis marks an omission):

... In the year 1971 a work of the experimental physicists Erwin J. Saxl and Mildred Allen was published in the journal Physical Review. Its title is 1970 Solar Eclipse as "Seen" by a Torsion Pendulum.
(E. J. Saxl / M. Allen : 1970 Solar Eclipse as "Seen" by a Torsion Pendulum, Physical Review, D3, p.823 (1971))
Both scientists are specialists for pendulum physics; the pendulum plays an important role in physics because it is a quite simple system ... Since 1953 both scientists had done pendulum experiments with ever increasing precision. In the work mentioned they report measurements done on March 7, 1970. On this day a solar eclipse happened and during the eclipse the oscillation time of the pendulum changed - it became larger. The difference is less than a thousandth part, therefore very accurate measurements and high experimental expertise are necessary to pin it down.

Of course, the authors of the publication tried at first to classify their measurement within the existing conception of the world; the position of the Moon during a solar eclipse could effect such a change by gravitational attraction: But the computations showed that this effect is a hundred thousand times smaller than observed. So the authors summarized: "All this leads to the conclusion that classical gravitational theory has to be modified, to interpret these experimental facts."

As we stated at the beginning of this chapter, measurements publicized in this way should actually be fitted into the scientific model of the world. Because they are in contradiction to existing theory, one of the three possibilities discussed in the second chapter should apply: The authors have tried in vain to use an additional hypothesis, therefore they suggest a modification of the theory.

Their suggestion remained without echo. Was their result not intersubjective? No, it was! Already in 1959, working on the same subject, Maurice F. C. Allais had publicized similar measurements, their results could therefore be checked by others. In spite of this, this work was never cited by other scientists (at least in the following years) in the scientific literature (naturally I say this with certainty only of journals covered by the Science Citation Index; but this is the most important and largest part of scientific journals). The measurements were simply ignored.

... (end of translation)

More on precision of calendars.


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