Almgren's Big Regularity Paper: Q-Valued Functions Minimizing Dirichlet's Integral and the Regularity of Area-Minimizing Rectifiable Currents Up to Codimension 2

by ; ; ; ;
Format: Hardcover
Pub. Date: 2000-09-01
Publisher(s): WORLD SCIENTIFIC PUB CO INC
List Price: $228.97

Rent Textbook

Select for Price
There was a problem. Please try again later.

Rent Digital

Rent Digital Options
Online:1825 Days access
Downloadable:Lifetime Access
$261.60
$261.60

New Textbook

We're Sorry
Sold Out

Used Textbook

We're Sorry
Sold Out

Summary

Fred Almgren created the excess method for proving regularity theorems in the calculus of variations. His techniques yielded Holder continuity except for a small closed singular set. In the sixties and seventies Almgren refined and generalized his methods. Between 1974 and 1984 he wrote a 1,700-page proof that was his most ambitious exposition of his ground-breaking ideas. Originally, this monograph was available only as a three-volume work of limited circulation. The entire text is faithfully reproduced here.

This book gives a complete proof of the interior regularity of an area-minimizing rectifiable current up to Hausdorff codimension 2. The argument uses the theory of Q-valued functions, which is developed in detail. For example, this work shows how first variation estimates from squash and squeeze deformations yield a monotonicity theorem for the normalized frequency of oscillation of a Q-valued function that minimizes a generalized Dirichlet integral. The principal features of the book include an extension theorem analogous to Kirszbraun's theorem and t

Table of Contents

Preface v
Introduction 1(17)
Principal results for area minimizing rectifiable currents
1(1)
Earlier related regularity results for area minimizing surfaces
2(1)
Geometric measure theory and the calculus of variations and the existence of area minimizing surfaces
2(1)
Why the results of I.1 are the best possible and the general necessity of singularities in area minimizing surfaces
3(1)
The spaces Q and Q and the mappings ρ and ξ
4(1)
Relations between currents and Q-valued functions
4(1)
Principal results for Q-valued functions minimizing Dirichlet's integral
5(1)
Relation between the nonparametric area integrand and Dirichlet's integrand
6(1)
The principal parameter of regularity; frequency of oscillation functions and their monotonicity
7(1)
Other applications of Q and Q (P,N)-valued functions
7(1)
Questions not settled and related questions
8(2)
Why this volume is so long
10(1)
Acknowledgments
10(1)
Summary of the principal themes by chapters
11(7)
Terminology 18(819)
General terminology (α(m), β(m), A(p, q), γ, γ0, ωT.1, graph, |||. |||, ±)
18(8)
Smoothing by convolution (φε, ψε, *, MF)
26(2)
Some coordinates, mean curvatures, and submanifolds (θ*, M*, NP*, Ms)
28(6)
Basic properties of Q and Q valued functions
34(57)
Definitions (Q, F, G, η, ξ, Q*, ρ, affine approximation)
34(6)
Theorem (the bilipschitzian correspondence ξ: Q → Q*)
40(4)
Theorem (the Lipschitz retraction ρ: RPQ→ Q*)
44(11)
Theorem (affine approximation and differentiation)
55(3)
Extensions of Lipschitz and piecewise affine Q valued functions, and integral currents associated with such functions
58(11)
Mappings of flat chains by Lipschitz Q valued functions
69(10)
Theorem (measurable representation of Lipschitz Q valued functions)
79(1)
Some estimates on tilted planes
79(4)
Theorem (some relations between several generalized ``excesses'')
83(2)
Proposition (continuous Q valued functions with interval domains)
85(6)
Properties of Dir minimizing Q valued functions and tangent cone stratification of mass minimizing rectifiable currents
91(134)
Definitions and terminology (Y2 (A, V), δY2 (A, V), Dir, dir)
91(1)
Theorem (existence of Dir minimizing functions)
92(1)
Elementary deformations of Q valued functions
93(2)
The squash deformations of a Q valued function
95(2)
The squeeze deformations of a Q valued function
97(3)
Theorem (the monotonicity of N and associated estimates on D and H)
100(7)
A comparison surface construction for Q valued functions on 2-dimensional domains
107(2)
A homogeneous comparison surface construction for general Q valued functions
109(1)
A standard modification procedure for members of Q
110(1)
The semi-retraction mappings Φ, Φ*: Q→Q
111(11)
Selection of constants for use in 2.12
122(1)
Theorem (an estimate of Dir in terms of dir for Dir minimizing functions)
123(8)
Theorem (the Holder continuity of Dir minimizing functions)
131(4)
Theorem (the analyticity of graphs of Dir minimizing Q valued functions except for closed sets of Hausdorff codimension two)
135(8)
Theorem (various a priori estimates on Dir minimizing and nearly Dir minimizing Q valued functions obtained from compactness type arguments)
143(32)
Theorem (observations about and examples of Dir minimizing functions)
175(6)
Definitions (rectifiable currents associated with Dir minimizing functions whose graphs have finite area)
181(1)
Theorem (reference statement of approximation of a nearly flat mass minimizing rectifiable current by the graph of a Lipschitz Q valued function)
182(1)
Theorem (limits of blowups of Dir decreasing sequences of Q valued approximations to increasingly flat mass minimizing rectifiable currents are Dirminimizing)
183(17)
Theorem (a sliced holomorphic branched covering is a Dir minimizing Q valued function)
200(5)
Examples and remarks (phenomena illustrated by holomorphic varieties)
205(3)
Theorem (an estimate of extra area in a cylinder compared with area in a ball for nearly flat rectifiable currents with controlled area density ratios)
208(5)
Corollary (E-1/2 blowups of Q valued functions approximating nearly flat mass minimizing rectifiable currents having density Q at 0 are a priori bounded)
213(4)
Corollary (relation between points where a nearly flat mass minimizing rectifiable current has density Q and points where the E-1/2 blowup of the Q valued approximating function has multiplicity Q)
217(1)
Definitions and terminology for Theorem 2.26 (generalized stratification of a mass minimizing rectifiable current according to the maximum dimension of the linear subspaces of maximal density among the, possibly several, tangent cones)
217(2)
Theorem (Hausdorff dimension estimates associated with the generalized stratification of mass minimizing rectifiable currents)
219(4)
Corollary (Hausdorff dimension estimates associated with the generalized stratification of mass minimizing rectifiable currents; except for a set of Hausdorff codimension two, each interior point of a mass minimizing rectifiable current has at least one oriented tangent cone which is an integral multiple of an oriented linear subspace)
223(1)
Remark (Hausdorff dimension estimates associated with a generalized stratification of integral varifolds having bounded generalized mean curvatures)
224(1)
Approximation in mass of nearly flat rectifiable currents which are mass minimizing in manifolds by graphs of Lipschitz Q valued functions which can be weakly nearly Dir minimizing
225(106)
Assumptions for sections 3.1 through 3.9 (special points Y in the support of an integral varifold having summable mean curvatures)
225(1)
Construction of the sets Yi, Xj, Xjk (special subsets of Y)
226(1)
Construction of the index set J
227(1)
Some estimates (distance and diameter estimates)
227(1)
Theorem (mass estimates associated with density estimates at Y)
228(3)
Theorem (separation of stationary integral varifolds with zero excess)
231(1)
Some choices of constants and properties of surfaces having small first variation distributions
232(1)
Theorem (initial approximation of nearly flat nearly stationary integral varifolds by graphs of locally Lipschitz Q valued functions)
233(7)
Corollary (global mass approximation of nearly flat nearly stationary integral varifolds by graphs of Lipschitz Q valued functions)
240(1)
Corollary (relations between the accuracy of global mass approximations of nearly flat nearly stationary integral varifolds and the Lipschitz constants of the approximating Q valued functions)
240(1)
Corollary (further accuracy---Lipschitz constant approximation relations)
241(1)
Corollary (further accuracy---Lipschitz constant approximation relations in terms of the E excess)
241(1)
Definition (Δ3.13)
242(1)
Corollary (further accuracy---Lipschitz constant approximation relations in terms of excess E and radius S for V stationary on M associated with Ms)
242(1)
Corollary (final accuracy---Lipschitz approximation relations in terms of E and S for V stationary on M associated with Ms)
243(1)
Theorem (mass relations between Q(l) valued functions and the associated Q valued functions induced by Φ §)
244(3)
Corollary (a comparison surface estimate for a piece of a mass minimizing rectifiable current)
247(2)
Corollary (a further comparison surface estimate)
249(1)
Corollary (an estimate for the amount of mass excess above a small set in a nearly flat rectifiable current which is mass minimizing in M associated with Ms for small S)
249(1)
First comparison surface constructions
250(12)
Portions of comparison currents obtained from the deformation theorem construction with isoperimetric inequality mass estimates
262(2)
Theorem (an estimate on the amount of Dir associated with steep slopes in a Q valued function mass approximating a mass minimizing rectifiable current)
264(4)
Terminology for sections 3.24, 3.25, and 3.26
268(1)
Theorem (an estimate on the amount of Dir associated with either steep slopes or a small domain in a Q valued function mass approximating a rectifiable current which is mass minimizing in M associated with Ms for small S)
269(9)
Second comparison surface construction
278(21)
Theorem (a mass excess estimate over a small set for a mass minimizing rectifiable current)
299(3)
Summary of constant selection and some new terminology
302(2)
First approximation theorem (a refined estimate for the mass approximation of nearly flat rectifiable currents which are mass minimizing in M by graphs of Lipschitz Q valued functions)
304(11)
Corollary (approximation estimates when M = Rm+l)
315(1)
Corollary (second approximation theorem with fewer hypotheses than 3.28)
316(2)
Lemma (an integral height estimate on approximating Q valued functions when the current approximated has a point with density Q)
318(2)
Theorem (mass minimizing rectifiable currents with small excess and relatively thick supports contain no interior points of density Q)
320(7)
Theorem (Q valued approximations to nearly flat rectifiable currents which are mass minimizing in M associated with Ms with S2 << are weakly nearly Dir minimizing)
327(4)
Approximation in mass of a nearly flat rectifiable current which is mass minimizing in a manifold by the image of a Lipschitz Q(Rm+n) valued function defined on a center manifold
331(352)
Proposition (a basic nonparametric area variational formula)
331(5)
Assumptions and terminology for sections 4.2 through 4.7 (a mass minimizing rectifiable current T is approximated by the graph of Lipschitz Q valued F with f = {r1 x {0}}# ˆ F and g = η ˆ f)
336(2)
Proposition (formulas for special first variations of T)
338(7)
Corollary (estimates on the Laplacian of ψε * g)
345(2)
Corollary (estimates on the Laplacian of ψε * g in weak form)
347(3)
Corollary (approximation of ψε * g)
350(3)
First center manifold approximation theorem (approximation of g by the sum of a harmonic function and a quadratic polynomial)
353(1)
Theorem on iterated spherical harmonic estimates
354(10)
First main approximation theorem (η ˆ F is approximatable by a cubic polynomial with errors depending on the number of homothetic expansions occuring earlier in an iteration process)
364(9)
Bases for Rm+n determined by linear mappings, orthonormalization, and orthogonal mappings determined by orthonormal bases
373(3)
Proposition (relations between linear subspaces and various associated mappings)
376(8)
Theorem on centerings of Q fold coverings in different coordinate systems
384(10)
Definitions and terminology (DIR, LIP)
394(1)
Theorem on Lipschitz constants and Dirichlet integrals of Q valued functions in different coordinate systems
395(5)
Proposition (first power integral inequalities on linear functions with rotated graphs)
400(2)
Assumptions, definitions and terminology for the remainder of Chapters 4 and 5 and some estimates
402(5)
Theorem (compatibility of the approximations of 4.9 with rotation and translations of coordinates and changes of scale)
407(21)
Some cubes in Rm, cubical subdivisions of [-1, 1]m, interpolation functions, admissible partitionings, and useful collections of cubes
428(4)
Center manifold differentiability criterion theorem
432(10)
Geodesic coordinates and associated estimates for surfaces which are nearly flat
442(9)
Definitions, terminology, and various estimates on several families of functions and associated sets
451(34)
Theorem on separation of mass minimizing integral currents
485(3)
Q(Rm+n) valued functions on a manifold N ((N, r) admissible functions f, interpolation procedures and estimates, evaluation of integrals)
488(19)
Further estimates on mass minimizing integral currents under conditions which permit approximation by Dir minimizing Q valued functions
507(22)
A refined procedure for approximating mass minimizing integral currents by Q(Rm+n) valued functions, especially when E is small
529(45)
A global procedure for approximating mass minimizing integral currents by Q(Rm+n) valued functions on a given manifold under various local approximation assumptions
574(35)
Some definitions and terminology for the center manifold construction (HT, EX)
609(12)
Some basic center manifold estimates and further estimates associated with HT and EX stopped cubes
621(27)
Construction of a cascade of functions for T4.27
648(5)
Construction of the center manifolds
653(3)
Additional center manifold terminology and estimates
656(9)
Some further definitions and terminology and associated observations (J4.32, S4.32, s(j), R4.32(j), Z4.32(j))
665(4)
Main approximation theorem for the approximation of a nearly flat mass minimizing integral current by a Q(Rm+n) valued function defined on a center manifold (f, N1, N2, Nr, δNr)
669(9)
Theorem (additional parameters associated with the main approximation theorem)
678(5)
Bounds on the frequency functions and the main interior regularity theorem
683(154)
Some definitions, terminology, and assumptions for sections 5.1 through 5.20
683(2)
Definitions, terminology, observations, and estimates on the frequency functions (D, H, Dj, Hj, Nj, Bj, Cj)
685(3)
Theorem estimating Nj2 in terms of Nj1 and the Bj and Cj
688(2)
Some derivative computations and estimates on H'(r) and Cj(s)
690(12)
A general first variation formula for T
702(1)
Estimates from the squash deformations
703(7)
Estimates from the squeeze deformations
710(19)
Some definitions and terminology (index of terms appearing in the formulas of 5.6 and 5.7)
729(1)
Proposition (a formula for B*(s) - D'j(s)/Dj(s))
730(2)
Some further terminology (L(r), HT(r), EX(r))L
732(1)
Some fundamental inequalities used to estimate B*j(s) - D'j(s)/Dj(s)
733(6)
Some conditional estimates on B*j(s) - D'j(s)/Dj(s)
739(16)
The basic inequality for the frequency functions Nj(s)
755(6)
Theorem (construction of a comparison surface of less mass in case the θm∞-2+ε measure of the set of points of density Q is relatively substantial)
761(28)
Theorem (regularity is implied by coincidence with the center manifold at any radius)
789(3)
Theorem (an a priori Nj(s) bound associated with radii near s4.32)
792(8)
Definitions and terminology (R*m, F*, mass minimizing tangent cones)
800(1)
Theorem (an a priori Nj(s) bound associated with nonflat tangent cones)
801(16)
Theorem (an a priori Nj(s) bound associated with radii near s4.32, Dir estimates associated with Nj(s), and a centering inequality)
817(2)
Selection and specification of various constants
819(3)
Theorem (at a density Q point admitting some flat tangent cone a mass minimizing rectifiable current is either regular there or the upper m-2+&epse; density there of &phis;m∞-2+&eps; restricted to its points of density Q is small)
822(10)
Main interior regularity theorem
832(3)
Boundary regularity and connectedness of mass minimizing integral currents (W.K. Allard)
835(1)
Almost sure uniqueness of mass minimizing integral currents in Rm+n (F. Morgan)
836(1)
Appendices 837(116)
A.1 Functions whose distribution first derivatives are square summable, harmonic functions, spherical harmonics, and inequalities relating Dirichlet integrals and zeros of functions
837(39)
A.1.1 Definitions and terminology (functions with square summable first derivatives)
837(2)
A.1.2 Theorem (general facts about functions with square summable first derivatives)
839(5)
A.1.3 Definitions and terminology (harmonic functions and spherical harmonics)
844(1)
A.1.4 Theorem (general facts about harmonic functions and spherical harmonics)
845(3)
A.1.5 Some terminology and elementary facts (including bilipschitzian parametrizations of hemispheres)
848(3)
A.1.6 Theorem (inequalities relating Dirichlet integrals and zeros of functions)
851(10)
A.1.7 Remarks
861(1)
A.1.8 Theorem (relations between Dirichlet integrals and Holder continuity)
861(5)
A.1.9 Proposition (supremum and integral relations for polynomial functions)
866(1)
A.1.10 Theorem (inequalities relating Dirichlet integrals and &phis;m∞-2+&eps; estimates on the zeros of functions)
867(9)
A.2 Convolution inequalities and interpolation estimates
876(9)
A.2.1 Theorem (convolution and square integrals)
876(5)
A.2.2 Proposition (interpolation and square integrals)
881(1)
A.2.3 Proposition (convolution, square integrals, and small sets)
882(2)
A.2.4 Proposition (a singular integral estimate)
884(1)
A.3 Estimates relating derivatives of various functions including functions with rotated graphs
885(31)
A.3.1 Definitions, terminology, and some observations (relations involving various derivatives of functions)
885(2)
A.3.2 Corollary (some inequalities for derivatives of functions)
887(1)
A.3.3 Implicit function theorem type estimates for functions with rotated graphs
888(6)
A.3.4 Lemma (G. Hunt) (orthogonal interchange of planes)
894(1)
A.3.5 Corollary to Theorem A.3.3
895(1)
A.3.6 First estimates on nearest point retractions
896(10)
A.3.7 Second estimates on nearest point retractions
906(5)
A.3.8 Proposition (estimates on first derivatives in curvilinear coordinate systems)
911(3)
A.3.9 Proposition (first estimates on linear functions with rotated graphs)
914(1)
A.3.10 Estimates on linear functions in terms of rotations of their graphs
915(1)
A.4 The nonparametric area integrand, mean curvatures, and Laplacians and further nearest point retraction estimates
916(9)
A.4.1 Proposition (the nonparametric area integrand)
916(1)
A.4.2 Proposition on mean curvature and Laplacians
917(2)
A.4.3 Third estimates on nearest point retractions
919(3)
A.4.4 Retractions onto a manifold preserving submanifold normals
922(3)
A.5 Some differential geometry of submanifolds of Euclidean space
925(15)
A.5.1 Some differential geometry of manifolds which are graphs of functions
925(11)
A.5.2 The differentiability of the exponential mapping of an embedded submanifold of Euclidean space (W.K. Allard)
936(4)
A.6 Varifolds and level sets and gradients of functions
940(7)
A.6.1 Varifolds determined by level sets of functions
940(6)
A.6.2 Estimates on gradients of functions
946(1)
A.7 Some measure and derivative estimates
947(6)
A.7.1 An inequality for size ∞ approximating measures
947(3)
A.7.2 Proposition (a derivative estimate for functions with deformed images
950(3)
References 953

An electronic version of this book is available through VitalSource.

This book is viewable on PC, Mac, iPhone, iPad, iPod Touch, and most smartphones.

By purchasing, you will be able to view this book online, as well as download it, for the chosen number of days.

Digital License

You are licensing a digital product for a set duration. Durations are set forth in the product description, with "Lifetime" typically meaning five (5) years of online access and permanent download to a supported device. All licenses are non-transferable.

More details can be found here.

A downloadable version of this book is available through the eCampus Reader or compatible Adobe readers.

Applications are available on iOS, Android, PC, Mac, and Windows Mobile platforms.

Please view the compatibility matrix prior to purchase.