which is equivalent to the following evolution inclusion
Find u ∈ V such that u
0
∈ W and
f(t) ∈ u
00
(t) + Au
0
(t) + Bu(t) + ∂
2
G(t, u
0
(t)) for a.e. t ∈ [0, T ]
u(0) = θ
u
0
(0) = θ.
(2.2)
In the sequel, to formulate our main results, we present some important definitions, lemmas, theo-
rems and hypotheses.
Definition 2.1 (see [10]) Let V be a real reflexive Banach space with its dual V
∗
. A mapping T :
D(T ) ⊂ V → 2
V
∗
is said to be pseudomonotone if the following conditions hold:
(a)
The set T u is nonempty, bounded, closed and convex for all u ∈ D(T );
(b) T is upper semi-continuous from each finite dimensional subspace F of V into V
∗
endowed with
the weak topology;
(c)
if {u
i
} is a sequence in D(T ) converging weakly to u of D(T ), and if u
∗
i
∈ T u
i
is such that
lim suphu
∗
i
, u
i
− ui ≤ 0, then for each element v ∈ D(T ) there exists u
∗
(v) ∈ T u with the property
that
lim infhu
∗
i
, u
i
− ui ≥ hu
∗
(v), u − vi.
Definition 2.2
(see [10]) Let V be a real reflexive Banach space with its dual V
∗
, L : D(L) ⊂ V → V
∗
be a linear densely defined maximal monotone mapping. A mapping T : D(T ) ⊂ V → 2
V
∗
is said to be
pseudomonotone with respect to D(L) if and only if (a), (b) and the following condition holds:
(d)
if {u
i
} ∈ D(L)∩D(T ) is such that u
i
→ u weakly in V , Lu
i
→ Lu weakly in V
∗
, u
∗
i
∈ T (u
i
), u
∗
i
→
u
∗
weakly in V
∗
and lim suphu
∗
i
, u
i
− ui ≤ 0, then u
∗
∈ T (u) and hu
∗
i
, u
i
i → hu
∗
, ui.
Definition 2.3 (see [3, 16, 23]) A mapping T : D(T ) ⊂ V → 2
V
∗
is said to have (S
+
) property (be of
class (S
+
)) if and only if (a), (b) and the following condition holds:
(e)
for any sequence {u
i
} in D(T ) converging weakly to u ∈ D(T ), w
i
∈ T (u
i
), the condition
lim suphw
i
, u
i
− ui ≤ 0
implies the strong convergence of {u
i
} to u in V and there exists a subsequence {w
n
i
} of {w
i
}
such that {w
n
i
} converges weakly to w ∈ T u in V
∗
.
It is well known that the conditions
kJ(u)k
V
∗
= kuk
V
and hJ(u), ui = kuk
2
V
, ∀u ∈ V (2.3)
determine a unique mapping J from V to V
∗
, which is called the duality mapping. In our case it is
bijective bicontinuous, strictly monotone and of class (S
+
). For more details we can refer to [23].
Definition 2.4
(see [1]) Let L : D(L) ⊂ V → V
∗
be a linear densely defined maximal monotone
mapping. A multivalued mapping T : D(T ) ⊂ V → 2
V
∗
is said to have (S
+
) property with respect to
D(L) (be of class (S
+
) with respect to D(L)) if and only if (a), (b) and the following condition holds:
4
http://www.paper.edu.cn