354 INDEX
edge path, 53
edges, 53
eigenvalue, 128, 132, 135, 255
eigenvalue problem, 259
Einstein field equation, 3
elliptic, 5, 43, 44
elliptic differential operator
– divergence type, 303
elliptic regularity theory, 240
ellipticity, 33, 245, 291
ellipticity condition, 46
energy, 142
energy norm, 147
equilibrium state, 2
estimates of J. Schauder, 291
Euler–Lagrange equations, 198, 200
example of Lebesgue, 75
existence, 6
existence problem, 297
extension of Sobolev functions, 250
exterior sphere condition, 74
first eigenvalue, 266
Fisher equation, 125
fixed point, 337
fundamental estimates of J. Moser,
306
fundamental solution, 269
gamma function, 100
Gierer-Meinhardt system, 131
global bound, 241
global error, 60
global existence, 123
Green function, 11, 14, 25, 57
– for a ball, 13
Green representation formula, 9
Green’s formulae, 7
– first Green’s formula, 7
– second Green’s formula, 7
Hadamard, 6
harmonic, 8, 14, 16, 19, 23, 24, 240
harmonic polynomials, 8
Harnack convergence theorem, 29,
64, 68
Harnack inequality, 28, 314
heat equation, 2, 79, 90, 110, 141,
149, 153
– semidiscrete approximation, 114
– strong maximum principle, 88
heat kernel, 82, 104, 153, 174
Hilbert space, 337
Hille–Yosida theorem, 165
H¨older continuous, 281
H¨older’s inequality, 340
Huygens principle, 146
hyperbolic, 5
infinitesimal generator, 156
inhomogeneous Neumann bound-
ary conditions, 254
initial boundary value problem, 84,
103, 106, 120
initial value problem, 91, 140, 144,
146, 154
integration by parts, 186
isolated singularity, 24
iteration argument, 247
Korteweg–de Vries equation, 2
Laplace equation, 1, 9, 53, 55, 92
– discrete, 55
– discretized, 114
– fundamental solution, 9
– weak solution, 197
Laplace operator, 1, 33, 175
– eigenvalues, 255
– rotational symmetry, 9
– transformation behavior, 199
Lax–Milgram theorem, 204
linear, 8
linear equation, 4
Liouville theorem, 27
Lipschitz continuous, 230, 281
local error, 60
local existence, 120
Markov process, 172