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Theory of Partial Differential Equations: Introduction and Course Outline

Jul 13, 2024

Lecture Series: Theory of Partial Differential Equations

Introduction

  • Unique theoretical perspective on partial differential equations (PDEs).
  • Unlike typical applied approaches found on platforms like YouTube.
  • Course will cover theoretical aspects mostly overlooked.
  • First video focuses on syllabus/content overview; subsequent videos will dive deeper.

Course Logistics

  • Frequency: 2-3 lectures per week (could be more).
  • Homework: Assignments provided after 4-5 lectures; solutions will be submitted and reviewed.
  • Resources: Link to GitHub page for syllabus and lectures.

Prerequisites

  • Advanced calculus
  • Advanced mathematical analysis
  • Functional analysis
  • Measure Theory
  • Note: Basic real analysis is generally sufficient.

Course Content Overview

Revision Topics

  • Functional Analysis: Banach and Hilbert spaces, dual spaces, Riez Representation Theorem, Lax-Milgram Theorem, weak and weak-star convergence.
  • Measure Theory: Lebesgue measure and integral.

Function Spaces

  • LP spaces
  • Convolutions and mollifiers
  • Functional inequalities (important in PDE analysis)

Sobolev Spaces and Weak Derivatives

  • Sobolev spaces and calculus
  • Poincaré inequality and embedding theorems

Linear Elliptic Equations

  • Existence and uniqueness of solutions
  • Regularity and elliptic regularity (e.g., Laplace’s equation)
  • Hormander’s function expansion

Fourier Series and Galerkin Method

  • Introduction to heat equation
  • Weak solutions for linear parabolic equations

Advanced Topics

  • Space of distributions
  • Fundamental solutions, Fourier transform, and L2 Hilbert spaces

Advanced PDE Topics (Optional)

  • Existence and uniqueness for Navier-Stokes equations (2D and 3D)
  • Recent studies and papers on Navier-Stokes (2D focus for practical discussions)
  • Reference to work by Jean Leray (1930s) and modern interpretations. Optional deep dive into Leray’s paper in French and its modern counterpart.

Recommended Textbooks

  1. Partial Differential Equations by Evans (widely used, available in market, Amazon, eBay).
  2. Introduction to Partial Differential Equations by David Borthwick (good mix of pure and applied perspectives).
  3. Infinite Dimensional Dynamical Systems by James C. Robinson (focus on existence and uniqueness, Galerkin method).

Next Steps

  • First lecture: Functional analysis and major results.
  • Second lecture: Measure theory and key results.
  • Future lectures: Deep dive into partial differential equations.

Stay tuned for the first lecture!