Re: Bulges

[Leigh Palmer <palmer@sfu.ca>]

> Finally, I do agree that Leigh has a good model for the real earth, but it
> is not what Mark and I thought Don was suggesting.

Don's point (as I take it) is that, while casting this problem in a
rotating frame of reference obviates the use of gratuitous stakes,
the rotation itself does very little to modify the bulges which are
present when only the gravitational terms are taken into account.
Since it is very easy to cast the problem in the rotating frame,
and since that really is a more nearly correct model of the Earth-
Moon system, there is little reason to approach it any other way.
As has been dramatically demonstrated here, there is very little
progress made toward "simplifying" the explanation when one models
the problem in less appropriate ways.

Now I must apologize for what I just did. I explained Don's point,
and that has been a problem here. I should probably not be
explaining to everyone what someone else means since I can't read
minds. I can read plain English, and I think Donald has explained
his points very clearly, at least more clearly than it would appear
I have been able to explain mine.

> One final thought and them I'm off this aspect of tides for the duration.
> If we have this much trouble understanding each other, is it any wonder
> students have problems.  Maybe it is because we aren't drawing pictures!
> At school I would never try to explain anything without drawing a picture.

I don't think that is really the problem. Our problem, if I read it
correctly, is that we are a bunch of prima donnas. I think we have,
to some small degree, lost our student status. Remember how we used
to thrash out tough problems with our fellow students? We would
make real progress, and even experience the thrill of discovery
when a concept finally clicked; the penny dropped like a twenty
dollar gold piece! The experience was so valuable that we all tell
our students now that they must work together on problems. We want
them to have the same thrilling experiences of discovery that we
had when we were students.

Now, however, we are all old professors. We are so infrequently
wrong in our daily activities that we become overconfident, and in
doing so I suspect we become refractory to discovery. That would
be a very sad result of this interaction, I feel. I learn from
these discussions. Perhaps I'd learn more if I were more open and
less defensive.

I'm going to try to practice what I preach.

Leigh