I've been doing a bit of googling and I came across this explanation of the tidal bulges on the
MadSci Network. It sounds a bit like your theory, JohnD:
Quote:
Indeed, one tide gets raised because the part of the Earth closest to the
Sun feels a stronger gravitational attraction than the rest of
the Earth. Sea water is gathered up and pulled towards the direction of the
Sun. On the other hand, the "backside" of the Earth, away from
the direction of the Sun feels a reduced gravity. As a result
sea water has tendency to escape the attraction of the Sun and
therefore gathers up in a tide on the backside of the Earth.
Although the use of the words "centrifugal force" tends to make physicists
uneasy, it can be a useful concept to figure out what is going on. In effect,
the Earth has a circular orbital velocity around the Sun which leads to
a centrifugal force which exactly balances the gravitational attraction
from the Sun at the center of the Earth. Regions of the Earth closer to the
Sun feel more gravitational attraction which is insufficiently compensated by
the "centrifugal force" from the orbit. Regions of the Earth further from the
Sun feel less gravitational attraction which is overcompensated by the orbital
"centrifugal force".
Marc Herant
Astronomy Mad Scientist Moderator
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My problem with Sawicki's explanation - correct though it is - is that it can only clear up the paradox of the tidal bulge on the far side of the Earth by speaking of negative forces. But gravity is attractive. If something under the influence of a gravitational force moves away from the source of that force, it can only be because of its velocity (like a rocket being launched, for instance).
If JohnD's theory is wrong, I wish someone would tell us
why, not
that, it is wrong.