Preface |
Introduction |
Dirichlet's Principle and the Boundary Value Problem of Potential Theory / I: |
Dirichlet's Principle / 1: |
Definitions |
Original statement of Dirichlet's Principle |
General objection: A variational problem need not be solvable |
Minimizing sequences |
Explicit expression for Dirichlet's integral over a circle. Specific objection to Dirichlet's Principle |
Correct formulation of Dirichlet's Principle |
Semicontinuity of Dirichlet's integral. Dirichlet's Principle for circular disk / 2: |
Dirichlet's integral and quadratic functionals / 3: |
Further preparation / 4: |
Convergence of a sequence of harmonic functions |
Oscillation of functions appraised by Dirichlet's integral |
Invariance of Dirichlet's integral under conformal mapping. Applications |
Dirichlet's Principle for a circle with partly free boundary |
Proof of Dirichlet's Principle for general domains / 5: |
Direct methods in the calculus of variations |
Construction of the harmonic function u by a "smoothing process" |
Proof that D[u] = d |
Proof that u attains prescribed boundary values |
Generalizations |
Alternative proof of Dirichlet's Principle / 6: |
Fundamental integral inequality |
Solution of variational problem I |
Conformal mapping of simply and doubly connected domains / 7: |
Dirichlet's Principle for free boundary values. Natural boundary conditions / 8: |
Conformal Mapping on Parallel-Slit Domains / II: |
Classes of normal domains. Parallel-slit domains |
Variational problem: Motivation and formulation |
Solution of variational problem II |
Construction of the function u |
Continuous dependence of the solution on the domain |
Conformal mapping of plane domains on slit domains |
Mapping of k-fold connected domains |
Mapping on slit domains for domains G of infinite connectivity |
Half-plane slit domains. Moduli |
Boundary mapping |
Riemann domains |
The "sewing theorem" |
General Riemann domains. Uniformization |
Riemann domains defined by non-overlapping cells |
Conformal mapping of domains not of genus zero |
Description of slit domains not of genus zero |
The mapping theorem |
Remarks. Half-plane slit domains |
Plateau's Problem / III: |
Formulation and solution of basic variational problems |
Notations |
Fundamental lemma. Solution of minimum problem |
Remarks. Semicontinuity |
Proof by conformal mapping that solution is a minimal surface |
First variation of Dirichlet's integral |
Variation in general space of admissible functions |
First variation in space of harmonic vectors |
Proof that stationary vectors represent minimal surfaces |
Additional remarks |
Biunique correspondence of boundary points |
Relative minima |
Proof that solution of variational problem solves problem of least area |
Role of conformal mapping in solution of Plateau's problem |
Unsolved problems |
Analytic extension of minimal surfaces |
Uniqueness. Boundaries spanning infinitely many minimal surfaces |
Branch points of minimal surfaces |
First variation and method of descent |
Dependence of area on boundary |
Continuity theorem for absolute minima |
Lengths of images of concentric circles |
Isoperimetric inequality for minimal surfaces |
Continuous variation of area of minimal surfaces |
Continuous variation of area of harmonic surfaces |
The General Problem of Douglas / IV: |
Solution of variational problem for k-fold connected domains |
Formulation of problem |
Condition of cohesion |
Solution of variational problem for k-fold connected domains G and parameter domains bounded by circles |
Solution of variational problem for other classes of normal domains |
Further discussion of solution |
Douglas' sufficient condition |
Lemma 4.1 and proof of theorem 4.2 |
Lemma 4.2 and proof of theorem 4.1 |
Remarks and examples |
Generalization to higher topological structure |
Existence of solution |
Proof for topological type of Moebius strip |
Other types of parameter domains |
Identification of solutions as minimal surfaces. Properties of solution |
Conformal Mapping of Multiply Connected Domains / V: |
Objective |
First variation |
Conformal mapping on circular domains |
Statement of theorem |
Statement and discussion of variational conditions |
Proof of variational conditions |
Proof that [phi](w) = 0 |
Mapping theorems for a general class of normal domains |
Formulation of theorem |
Variational conditions |
Conformal mapping on Riemann surfaces bounded by unit circles |
Variational conditions. Variation of branchpoints |
Uniqueness theorems |
Method of uniqueness proof |
Uniqueness for Riemann surfaces with branch points |
Uniqueness for classes [characters not reproducible] of plane domains |
Uniqueness for other classes of domains |
Supplementary remarks |
First continuity theorem in conformal mapping |
Second continuity theorem. Extension of previous mapping theorems |
Further observations on conformal mapping |
Existence of solution for variational problem in two dimensions |
Proof using conformal mapping of doubly connected domains |
Alternative proof. Supplementary remarks |
Minimal Surfaces with Free Boundaries and Unstable Minimal Surfaces / VI: |
Free boundary problems |
Unstable minimal surfaces |
Free boundaries. Preparations |
General remarks |
A theorem on boundary values |
Minimal surfaces with partly free boundaries |
Only one arc fixed |
Remarks on Schwarz' chains |
Doubly connected minimal surfaces with one free boundary |
Multiply connected minimal surfaces with free boundaries |
Minimal surfaces spanning closed manifolds |
Existence proof |
Properties of the free boundary. Transversality |
Plane boundary surface. Reflection |
Surface of least area whose free boundary is not a continuous curve |
Transversality |
Unstable minimal surfaces with prescribed polygonal boundaries |
Unstable stationary points for functions of N variables |
A modified variational problem |
Proof that stationary values of d(U) are stationary values for D[characters not reproducible] |
Generalization |
Remarks on a variant of the problem and on second variation |
Unstable minimal surfaces in rectifiable contours |
Preparations. Main theorem |
Remarks and generalizations |
Continuity of Dirichlet's integral under transformation of [characters not reproducible]-space |
Bibliography, Chapters I to VI |
Some Recent Developments in the Theory of Conformal Mapping / M. SchifferAppendix: |
Green's function and boundary value problems |
Canonical conformal mappings |
Boundary value problems of second type and Neumann's function |
Dirichlet integrals for harmonic functions |
Formal remarks |
The kernels K and L |
Inequalities |
Conformal transformations |
An application to the theory of univalent functions |
Discontinuities of the kernels |
An eigenvalue problem |
Kernel functions for the class [characters not reproducible] |
Comparison theory |
An extremum problem in conformal mapping |
Mapping onto a circular domain |
Orthornormal systems |
Variation of the Green's function |
Hadamard's variation formula |
Interior variations |
Application to the coefficient problem for univalent functions |
Boundary variations |
Lavrentieff's method |
Method of extremal length |
Concluding remarks |
Bibliography to Appendix |
Index |
Preface |
Introduction |
Dirichlet's Principle and the Boundary Value Problem of Potential Theory / I: |