Cover of Book

Differential Geometry and its Applications

by

John Oprea


Second Edition Available November 2003! Cover of 2nd Edition




Enneper's Surface

Enneper's Surface

by

MapleV4



The point of this book is to mix together differential geometry, the calculus of variations and some applications (e.g. soap film formation, constrained particle motion, Foucault's pendulum) to see how geometry fits into science and mathematics. The book includes many Maple procedures that allow students to view geometry and calculate things such as Euler-Lagrange equations.

In particular, Chapter 5 on geodesics contains a procedure to plot geodesics on surfaces and this procedure gives beautiful illustrations of the Clairaut relation for example. The same type of procedure also allows students to visualize the motion of a particle constrained to move in bowls (of various shapes) under gravity. These are the kinds of connections between geometry and applications which I like and which I think are important for students to see. Here is an example of a geodesic on the surface of revolution obtained by revolving the Witch of Agnesi about the x-axis. Notice how the geodesic is bounded between two parallels. This is the Clairaut relation in action. By the way, the following picture is only a first attempt at using Maple to create a JPEG file for the web --- better things will surely come later!

Geodesic on the
Whirling Witch

The picture above was created by a procedure called `plotgeo' which may be found in Chapter 5 of the book. Here are a few other examples of geodesics on surfaces constructed from this procedure.
Geodesic on a TorusGeodesic on a Torus Geodesic on a CylinderGeodesic on a Cylinder

Some Maple Worksheets
For information about soap films and minimal surfaces, see The Soap Film Page.


MWS Files for the Mylar Balloon
The Maple worksheet on the balloon is obtained by clicking on either Geodesics on the Mylar Balloon for Maple 7
or
Geodesics on the Mylar Balloon for Maple 8.
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