On 4 Feb 2026 13:31:48 GMT,
ram@zedat.fu-berlin.de (Stefan Ram) wrote:
quadi <quadibloc@ca.invalid> wrote or quoted:
Of course, though, the Ptolemaic geocentric solar system is not
disproved
by this.
Basically, all coordinate systems are on equal footing as long
as you can link them with diffeomorphisms. So yeah, you can
pick a system where Earth always has the coordinates (0,0,0),
meaning it's "at rest", but you can't use one where Earth is
flat, since there's no diffeomorphism that turns a sphere into
a plane or a surface built from one.
You guys do realize that /Ptolemy/ showed the Earth was round (just
immobile and at the center of everything) by pointing out that the
"horizon" would have no meaning on a Flat Earth: the fixed stars are
so far away that they would /all/ be visible regardless of lattittude,
right?
--
"Here lies the Tuscan poet Aretino,
Who evil spoke of everyone but God,
Giving as his excuse, 'I never knew him.'"
--- PyGate Linux v1.5.11
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)