MAT 1061 Partial Differential Equations II (Winter 2026)

This course, which is a sequel to MAT 1060, will be an introduction to the beautiful theory of elliptic and parabolic PDEs, with a focus on techniques to analyze nonlinear equations motivated by examples from geometry and physics.

Instructor: Bob Haslhofer

Contact Information: roberth(at)math(dot)toronto(dot)edu

Website: http://www.math.toronto.edu/roberth/pde2.html

Lectures: Monday and Wednesday 12:30--2:00 in BA6183

Office hours: Wednesday 2:30--3:30 in BA6208

Grading Scheme: attendance and participation 20%, assignments 30%, final exam 50%

Assignments: via crowdmark

Final Exam: TBA

Main References: The main textbook is "Partial Differential Equations" by L.C. Evans.
I'll also provide lecture notes for selected topics.

Secondary References:
D. Gilbarg, N.S. Trudinger: Elliptic Partial Differential Equations of Second Order, Springer, 2001
G.M. Lieberman: Second Order Parabolic Differential Equations, World Scientific Publishing, 1996
M. Taylor: Partial Differential Equations III. Nonlinear Equations, Springer, 1996
M. Struwe: Plateau's problem and the calculus of variations, Princeton University Press, 1988
L. Simon: Schauder estimates by scaling, Calc. Var. PDE 5, no.5, 391--407, 1997
B. Osgood, R. Phillips, P. Sarnak: Extremals of Determinants of Laplacians, J. Funct. Anal. 80, no.1, 148--211, 1988
P. Li, S.T. Yau: On the parabolic kernel of the Schroedinger operator, Acta Math. 156, no. 3--4, 153--201, 1986


Topics to be covered:
1. Elliptic equations: calculus of variations, existence of minimizers, regularity (Hilberts 19th problem), Lagrange multipliers, mountain pass lemma, applications to semilinear elliptic PDEs, Pohozaev identity, Plateau's problem, surfaces of prescribed curvature.
2. Parabolic equations: TBA


Weekly schedule:

Week 1
Plateau's problem, first and second variation, existence of minimizers (Evans 8.1 and 8.2) notes

Week 2
review of Sobolev spaces (Notes on Sobolev spaces), weak solutions, energy estimates, regularity (Evans 8.2 and 8.3) notes

Week 3
Schauder estimates (Notes on Schauder estimates), DeGiorgi-Nash-Moser estimates (Notes on epsilon-regularity) notes

Week 4
Lagrange multipliers, min-max theory (Evans 8.4 and 8.5) notes

Week 5
applications of min-max theory, Pohozaev identity (Evans 8.5 and 9.4) notes

Week 6
Plateau's problem, surfaces with prescribed curvature (Struwe's book and Osgood-Phillips-Sarnak paper) notes

Week 7
intro to parabolic PDEs, time-dependent function spaces, weak solutions (Evans 5.9 and 7.1) notes

Week 8
existence and regularity, weak and strong maximum principle (Evans 7.1) notes

Week 9
differential and classical Harnack inequality, existence for nonlinear parabolic PDEs (Li-Yau paper, Evans 9.2) notes

Week 10--12
TBA