## A History of the Stability Problem, From the Time of
Newton to the Time of Laplace (1687-1787)

Briefly, my thesis traces the history of the problem of proving (or
not) that the solar system is dynamically stable over a long period of
time (like geological eras), between the publication of the Principia
of Newton (1687) to the works of Laplace (1787).

The early period (until about 1760, actually) was concerned with
the idea that the interplanetary medium offered some resistance to the
motion of the planets, and that through this resistance, the planets
would eventually spiral into the sun. (As this would involve the
total destruction of the entire solar system, the Earth, and life
itself, most would consider this to be a bad thing, though for some, it was consonant with their theological
beliefs.)

Thereafter, Joseph Louis Lagrange and later, Pierre Simon
Laplace, set about to show that the gravitational interaction between
the planets would not disrupt their regular motion around the sun.
Though Laplace is usually given credit for the first "proof" that the solar system is stable, a
portion of my thesis is devoted to showing that much of Laplace's work
is either based on Lagrange, or is anticipated by Lagrange, who is
shown on the right.

For more on my thesis, you can download it. In one of the
appendices (called chapter12.tex) I have one of my few original
contributions to mathematics: a purely geometric demonstration of the
equilateral solution to the Lagrange problem, using Newtonian methods.
When I think enough people have HTML 3.0 capable browsers, I'll have
more pages on line.

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