Differential Geometry III

MATH3021

Lecturer : Norbert Peyerimhoff

Term : Michaelmas 2012/13

Lectures :
  • Wednesdays, 9:00 in CG91
  • Thursdays, 9:00 in CG93

Problem Classes :

  • Wednesday, 7 November, 13:00 in CG83
  • Wednesday, 28 November, 13:00 in CG83

Literature

The following is a list of books on which the lecture is based. They are available in the library. Although we will not follow a books strictly, the material can be found in them and they may sometimes offer a different approach to the material.

Relevant Books:
  • LM Woodward and J Bolton, Differential Geometry Lecture Notes. Copies are available from the Maths office free of charge.
  • M doCarmo, Differential Geometry of Curves and Surfaces

Assignments

Questions can be found at http://www.maths.dur.ac.uk/~dma0np/diffgeom1213/diffgeoproblems.pdf



Homework
Date Hand in Solutions
Questions 2, 6 (i) (ii), 10 (i) (ii) (iii) 24.10.2012 1.11.2012 Solutions pdf
Questions 17, 19 (i) (ii), (iii), 29, 36 29.11.2012 12.12.2012 Solutions pdf


Content of Lectures

Date Content
Wednesday, 10 October 2012 (Week 1) Motivation (curves, surfaces and aims of the course), notions of curves (smooth, trace, tangent vector, regular, unit tangent vector, unit speed, singular), examples
Thursday, 11 October 2012 (Week 1) parameter change, arc-length, arc-length parametrisation, examples
Wednesday, 17 October 2012 (Week 2) Curvature of a space curve, tangent vectors, normal vectors and curvature of a unit speed plane curve, examples, curvature for plane curves with arbitrary parametrisation, examples
Thursday, 18 October 2012 (Week 2) Vertices and inflection points of plane curves, examples, 4 vertex Theorem, Fundamental Theorem of local theory of plane curves
Wednesday, 24 October 2012 (Week 3) Radius and centre of curvature, evolute, examples, involute, example, curvature of a space curve
Thursday, 25 October 2012 (Week 3) unit tangent, unit normal and binormal vector of a curve, osculating plane, moving frame, Serret-Frenet equations, curvature and torsion for non unit speed space curves
Wednesday, 31 October 2012 (Week 4) continuation: curvature and torsion for non unit speed space curves, geometric meaning of curvature and torsion, vanishing torsion for space curves in a plane
Thursday, 1 November 2012 (Week 4) fundamental theorem of local theory of space curves, Taylor expansion of space curves up to order 3 in terms of curvature and torsion, open sets in R^n, examples of smooth functions R^n -> R^m, definition of Jacobi matrix and derivative
Wednesday, 7 November 2012 (Week 5) Examples of Jacobi matrices and derivatives, implicit function theorem, example, definition of a surface, local parametrisation and coordinate chart
Thursday, 8 November 2012 (Week 5) Graphs as surfaces, examples, example of sphere as being parametrised with 6 local parametrisations, example of sphere as preimage of a function
Wednesday, 14 November 2012 (Week 6) Regular values and critical points, surfaces as preimages of regular values, examples, definition of a diffeomorphism
Thursday, 15 November 2012 (Week 6) Change of parametrisations, surfaces of revolution, parallels, meridians, canal surfaces, ruled surfaces, examples
Wednesday, 21 November 2012 (Week 7) One sheeted hyperboloid as doubly ruled surface, tangent vectors and tangent plane
Thursday, 22 November 2012 (Week 7) Examples of surfaces and their coordinate tangent vectors, tangent plane of an implicitly defined surface, first fundamental form (FFF), coefficient functions E,F,G of first fundamental form in a local parametrisation
Wednesday, 28 November 2012 (Week 8) Coefficients of FFF for surface of revolution, arc-length of curves in surfaces, upper half-space model of the hyperbolic plane, angle between coordinate curves
Thursday, 29 November 2012 (Week 8) Area of a region in a surface, examples (zone of a sphere, torus of revolution)
Wednesday, 5 December 2012 (Week 9) Further examples of areas (hyperbolic plane, helicoid), definition of a smooth map between surfaces, independence of this definition from the local parametrisation, definition of Gauss map, Gauss map for local parametrisations
Thursday, 6 December 2012 (Week 9) Gauss map and the orientability problem, examples of Gauss maps, the Moebius strip and non-orientability
Wednesday, 12 December 2012 (Week 10) Derivative of a smooth map as a linear map, independence of the derivative of the local parametrisation, examples itself
Thursday, 13 December 2012 (Week 10) Derivative of the Gauss map as a linear map from the tangent space of a surface to itself, definition of a local and a global isometry, example

Last modified: 29.10.2012