Re: Riemann geometry, chicken or the egg?

In article <7tj1k2h3iemc5m7iqnq8gn4lch1uft1gjk@xxxxxxx>,
bootlace <anonymous@xxxxxxxxxx> wrote:
On Thu, 26 Oct 2006 03:30:00 GMT, Gerry Myerson
<gerry@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

I believe that doing geometry without an eye to physics goes back
to ancient Greece. Conic sections were studied pretty much for
their own sake.

The motion of planets and asteroids were available to the greeks and
it seems logical they might have wondered how you could describe an
ellipse.

Asteroids???
The Greeks knew seven planets (Sun, Moon, Mercury, Venus, Mars,
Jupiter, Saturn), but not asteroids. Some Greeks did have a
heliocentric system, but the idea that the orbits were ellipses
seems not to have occurred to anybody before Kepler.

Robert Israel israel@xxxxxxxxxxx
Department of Mathematics http://www.math.ubc.ca/~israel
University of British Columbia Vancouver, BC, Canada
.

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