Professor of Mathematics
Nov 24 2009:
Homework set 6 is available for download from the right-most column of the class schedule. It is due in class on Tuesday, December 8.
Have a great Thanksgiving break! When we return we will finish Chapter 7 with a discussion of weak convergence and then move on to highlights from Chapters 8 and 9 to finish the semester.
Here are some notes and solutions:
| Week | Meeting | Date | In Class | Homework |
|---|---|---|---|---|
| Week 1 | Lecture 1 | Tuesday, September 8 | Course Introduction. Initial and boundary value problems for partial differential equations as models for physical processes. | |
| Lecture 2 | Thursday, September 10 | Chapter 1. The Dirac delta "function". Basic distribution theory. Test functions. Regular and singular distributions. | ||
| Week 2 | Lecture 3 | Tuesday, September 15 | Comparison of distributions and functions: equality of distributions on open sets and approximation of distributions by smooth functions. Basic operations with distributions: (i) linear combinations, (ii) products of smooth functions and distributions, (iii) translations of distributions, (iv) dilations of distributions, (v) differentiation of distributions. | |
| Lecture 4 | Thursday, September 17 | Convergence of distributions. Distributions describing the regularization of divergent integrals. | ||
| Week 3 | Lecture 5 | Tuesday, September 22 | Review of classical Fourier series. Orthogonality of harmonics, formula for Fourier coefficients, Bessel's inequality, and smoothness of a function versus decay of its Fourier coefficients. Uniform convergence of Fourier series with rapidly decaying coefficients (to something...). | |
| Lecture 6 | Thursday, September 24 | Classical Fourier series, continued. Pointwise and uniform convergence of the Fourier series of a continuous and piecewise smooth function to the function itself. Distributional Fourier series and the Poisson summation formula. | ||
| Week 4 | Lecture 7 | Tuesday, September 29 | Chapter 2. Introduction to differential equations in distributions. Formal adjoints. Distributional, weak, and classical solutions of linear differential equations. The simplest differential equation: u'=f. Introduction to Green's functions and fundamental solutions. | Homework Set 1 Due |
| Lecture 8 | Thursday, October 1 | Existence of Green's functions. Use of Green's functions to solve inhomogeneous problems. | ||
| Week 5 | Lecture 9 | Tuesday, October 6 | Chapter 3. The classical theory of Fourier transforms. | |
| Lecture 10 | Thursday, October 8 | Distributions of slow growth (AKA tempered distributions). Generalized Fourier transforms. | ||
| Week 6 | Lecture 11 | Tuesday, October 13 | Applications to partial differential equations. | Homework Set 2 Due |
| Lecture 12 | Thursday, October 15 | Chapter 4. Basic concepts of vector spaces. Normed linear spaces. Examples. | ||
| Week 7 | Tuesday, October 20 | FALL BREAK | ||
| Lecture 13 | Thursday, October 22 | Topological notions. Convergence and completeness. Equivalence of norms. Banach spaces. | ||
| Week 8 | Lecture 14 | Tuesday, October 27 | Chapter 5. Linear and nonlinear operators on vector spaces. | Homework Set 3 Due |
| Lecture 15 | Thursday, October 29 | Contraction operators and The Contraction Mapping Theorem. Neumann series for operator inverses. Midterm Exam: 6-8 PM, 3088 East Hall |
||
| Week 9 | Lecture 16 | Tuesday, November 3 | Applications. Newton's Method. Picard iteration. | |
| Lecture 17 | Thursday, November 5 | Applications continued. Solution of boundary-value problems for partial differential equations by using the "wrong" Green's function. Nonlinear diffusive equilibrium. | ||
| Week 10 | Lecture 18 | Tuesday, November 10 | Chapter 7. Inner product spaces. Hilbert spaces. Orthogonal bases and the Gram-Schmidt process. | Homework Set 4 Due |
| Lecture 19 | Thursday, November 12 | Orthogonal expansions. The Bessel, Parseval, and Riesz-Fischer Theorems. | ||
| Week 11 | Lecture 20 | Tuesday, November 17 | Linear functionals, weak convergence in Hilbert space, and the Riesz Representation Theorem. | |
| Lecture 23 | Thursday, November 19 | Chapter 12. Construction of L2 as a distributional Hilbert space without Lebesgue integration theory. Sobolev spaces. | ||
| Week 12 | Lecture 22 | Tuesday, November 24 | Chapter 8. The algebra of bounded operators on normed spaces. | Homework Set 5 Due |
| Thursday, November 26 | THANKSGIVING BREAK | |||
| Week 13 | Lecture 23 | Tuesday, December 1 | Selfadjoint operators and the eigenvalue problem. Sturm-Liouville theory. | |
| Lecture 24 | Thursday, December 3 | Compact operators. Examples. | ||
| Week 14 | Lecture 25 | Tuesday, December 8 | Chapter 9. The Spectral Theorem for compact selfadjoint operators. Application to Sturm-Liouville problems. | Homework Set 6 Due |
| Lecture 26 | Thursday, December 10 | The Fredholm alternative. | ||
| Week 15 | Wednesday, December 16 | FINAL EXAM |