The concept of gravity came into being in ancient times as a terrestrial concern associated with the practicalities of “weight.” A great leap forward came in the early 1600s with the important theoretical speculations of Johannes Kepler. This article focuses on his prescient theory of gravity which guided the later progress of a number of scholars including Roberval, Hooke, and Newton. And yet, Kepler's remarkable contribution to gravitational theory has been almost completely overlooked in the contemporary scientific literature.
References
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Gerald
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James T.
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Eugene
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For an English translation of Commentariolus see <http://dbanach.com/copernicus-commentarilous.htm>
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Anton
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Reference 15, Book 2, Chap. II.
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Max
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Reference 24, Dover Publications p. 139, footnote. See also
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Reference 33, Gesammelte Werke, Epitome of Copernican Astronomy. In Latin at <http://kepler.badw.de/kepler-digital.html> where it appears in Vol. VII, p.
93
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Edward
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. <https://www.loc.gov/resource/rbctos.2017gen10144/?sp=1>. The necessity for a grasping force may have come from Kepler's conviction that “the motions of heavy bodies are rectilinear, so that this kind of order, I mean [motion in] a straight line, is somehow a property of heavy bodies…” The implications for the Law of Inertia are obvious.36.
Reference 33, Gesammelte Werke. My translation. In Latin at <http://kepler.badw.de/kepler-digital.html> where it appears in Vol. XV, p.
240
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See also,
Johannes
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William
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40.
Johannes
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Wallis
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45.
Reference 40, p.
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Reference 35, Appendix H provides a summary of several aspects of Kepler's theory of gravity. For the complete Latin original of Somnium view online: <https://archive.org/stream/joanniskepleria00frisgoog#page/n8/mode/2up>.
47.
48.
Reference 35, p.
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Reference 35, Note 66, p.
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Reference 29, third dialogue, p.
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Reference 35, Note 202, p.
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.52.
Edward
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34
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Reference 40, p.
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Epitome Astronomiae Copernicanae, Book IV, p.
517
, of the first edition. This was published as a separate volume in 1622, four years after Books I–III. Hence it is Vol. 2, though paginated continuously from Vol. 1. It can be viewed on line in Latin at <http://kepler.badw.de/kepler-digital.html> where it appears in Vol. VII on p. 300; or <http://archive.org/details/bub_gb_FaMM9-9BkkgC> (My translation).55.
Pierre
de Fermat
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Henry
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Thomas
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Robert D.
Purrington
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(Birkhäuser
, Basel, Switzerland
, 2009
), p. 168
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