
Bounded State Problems 325
φ
j
k
(t))dt remain bounded as k → ∞. If we next replace h by ζ(t) +
[∇G(t,
e
φ
ǫ
(t)) · ζ]ξ
ǫ
, ζ(0) = ζ(t
1
) = 0 we obtain
J(
e
φ
ǫ
, ζ) + J(
e
φ
ǫ
, [∇G(·,
e
φ
ǫ
(·)) · ζ]ζ
ǫ
) = 0
Now, using (11.6.9) and (11.6.10) we obtain
ψ(ǫ; t) + λ(ǫ; t)∇G(t,
e
φ
ǫ
(t)) (11.6.11)
=
Z
t
0
n
−[ψ(ǫ; s) + λ(ǫ; s)∇G(s,
e
φ
ǫ
(s))] · f
1
(ǫ; s) + f
0
1
(ǫ; s)
+ λ(ǫ; s)∇G(s,
e
φ
ǫ
(s)) · f
1
(ǫ; s)
+ λ(ǫ; s)
"
d∇G(s,
e
φ
ǫ
(s))
ds
#
+ 2(
e
φ
′
ǫ
(s) − φ
′
0
(s)) · f
1
(ǫ; s)
)
ds + c
ǫ
We next obtain an ǫ-minimum principle. From Remark 11.6.6 we know
that F
K(ǫ)
(
e
φ
ǫ
, ν
ǫ
) minimizes F
K(ǫ)
(
e
φ, ν) over B(ǫ). For 0 < ǫ < ǫ
′
< ǫ and
0 ≤ θ ≤ 1, let
ν(θ) = ν
ǫ
+ θ(ν − ν
ǫ
)
Since kν
ǫ
−ν
0
k < ǫ ∃ θ
0
> 0 such that 0 ≤ θ ≤ θ
0
implies ...