On Mar 13, 12:00*pm, Mike Jr wrote:

Why set aside *'convection cells' in the earth? *Can't differential
rotation and convection cells be happening in the earth's interior at
the same time?

It's worse than that.

It is true that what he terms "differential rotation" is observed on
Jupiter or on the Sun. But this phenomenon is _caused_ by convection
cells, and is analogous to the trade winds on Earth.

Since the convection bands on the Sun aren't driven by differences in
solar radiation at the equator and the poles - the Sun is just about
equally bright all over - I suppose one can't discount Coriolis forces
producing convection bands in the Earth's interior. However, what with
the rigid crust being in contact with the mantle on the outside, and
the rather high viscosity of the mantle, I don't think that anyone
expects recognizable convection banding in the interior of the Earth.

Oriel36, though, doesn't let little things like the lack of a physical
mechanism stop him. Since differential rotation is seen on Jupiter and
on the Sun, he deduces it in the Earth's mantle simply by analogy.
According to him, analogy and intuition - with some conscientious
authority constraining it - is the path to knowledge. Instead, science
today works by attempting to find direct physical causes for things
whenever possible - it is reductionistic - and the only authority it
uses is Nature itself to keep it in line with reality - it is
empirical. Oriel36 is very unhappy with this, and he thinks that
science today is very much on the wrong track.

It would take a whole textbook on the history of science to explain
why he is wrong, and why science the way it is now is following the
only path of those that have been tried (and Oriel36 is advocating the
return to a path that _has_ been tried, and found wanting, the path
that ultimately led to the persecution of Galileo) that provides a
route to sure progress.

It is only one path, and we may well be missing things that will have
to be explained and discovered in some other way, but abandoning it
for a failed path isn't the way to address the limitations fo science.

John Savard