WEBSITE for MATH 426
Introduction to Modern Geometry, Spring 2004, Penn State
Instructor
Professor Mohammad Ghomi
- Lecture Notes 0
Basics of Euclidean Geometry, Cauchy-Schwarz inequality
- Lecture Notes 1
Definition of curves, examples, reparametrizations, length
- Lecture Notes 2
Curvature, tangent
- Lecture Notes 3
Curves of constant curvature, the principal normal, oschulating circle,
signed curvature, turning angle, winding number, Hopf's theorem
- Lecture Notes 4
Radius of Curvature, total curvature, convexity
- Lecture Notes 5
The four vertex theorem, isoperimetric inequality
- Lecture Notes 6
Torsion, Frenet-Seret frame, helices, spherical curves
- Lecture Notes 7
Fenchels theorem on total curvature, and Milnors theorem on total curvature of knots (Not yet typeset)
- Lecture Notes 8
Definition of surface, differential map
- Lecture Notes 9
Gaussian curvature, Gauss map, shape operator, coefficients of the first and second fundamental forms, curvature of graphs
- Lecture Notes 10
Interpretations of Gaussian curvature as a measure of local convexity, ratio of areas, and products of principal curvatures.
- Lecture Notes 11
Gauss's Theorema Egregium (Not yet typeset)
- Lecture Notes 12
Gauss-Bonnet theorem (Not yet typeset but contains the exercises)
- Lecture Notes 13
A few more exercises.
- CrossProducts.nb
How to prove various identities involving dot product and cross products, including the three dimensional version of the Pythagorean theorem.
- GraysProgs.nb
This notebook loads up all the miniprograms written by Alfred Gray to accompany his book on Curves and Surfaces.
- PlanarCurves.nb
Dozens of parametrizations for various curves; programs for computing curvature, length, and winding number; plotting programs for coloring a curve according to its curvature, and programs for plotting curves determined by a given curvature function; several animation programs including cycloid, tractrix and trochoids.
- SpaceCurves.nb
Dozens of parametrizations for various curves; programs for computing curvature, torsion and length; programs for coloring a curve by its curvature or torsion; programs for plotting the tangential, normal, and binormal, spherical images.
- Surfaces.nb
Dozens of parametrizations for various surfaces; programs for computing Gauss and mean curvature; programs for coloring a surface by its Gauss or mean curvature.