2566 CHAPTER 76. IMPLICIT STOCHASTIC EQUATIONS

≤∫

supt∈[0,T ]

⟨Bun,un⟩1/2 (t)

((∫ T

0∥Φn−Φ∥2

L2dt)1/2

)dP

(∫Ω

supt∈[0,T ]

⟨Bun,un⟩(t)

)1/2(∫Ω

∫ T

0∥Φn−Φ∥2

L2dt)1/2

From 76.4.32

≤C(∫

∫ T

0∥Φn−Φ∥2

L2dt)1/2

which converges to 0.Return now to the equation solved by un in 76.4.37. Apply the Ito formula to this one.

This yields for a.e. t,

12⟨Bun (t) ,un (t)⟩−

12⟨Bu0n,u0n⟩+

∫ t

0⟨A(ω)un,un⟩ds =

12

∫ t

0⟨BΦn,Φn⟩ds

+∫ t

0⟨ f ,un⟩ds+

∫ t

0

(Φn ◦ J−1)∗Bun ◦ JdW (76.4.45)

Assume without loss of generality that T is not in the exceptional set. If not, consider allT ′ close to T such that T ′ is not in the exceptional set.∫ T

0⟨(λB+A(ω))un,un⟩ds

=12⟨Bu0n,u0n⟩−

12⟨Bun (T ) ,un (T )⟩+

∫ T

0⟨ f ,un⟩ds

+∫ T

0

(Φn ◦ J−1)∗Bun ◦ JdW +

12

∫ T

0⟨BΦn,Φn⟩ds+

∫ T

0⟨λBun,un⟩ds

Now it follows from 76.4.42 applied to t = T and the above lemma that

lim supn→∞

∫ T

0⟨(λB+A(ω))un,un⟩ds

≤ 12⟨Bu0,u0⟩−

12⟨Bu(T ) ,u(T )⟩+

∫ T

0⟨ f ,u⟩ds

+∫ T

0

(Φ◦ J−1)∗Bu◦ JdW +

12

∫ T

0⟨BΦ,Φ⟩ds+

∫ T

0⟨λBu,u⟩ds

and from 76.4.43, the expression on the right equals∫ T

0 ⟨λBu+ξ ,u⟩ds. Hence

lim supn→∞

∫ T

0⟨(λB+A(ω))un,un⟩ds≤

∫ T

0⟨λBu+ξ ,u⟩ds

Then since λB+A(ω) is monotone and hemicontinuous, it is type M and so this requiresA(ω)u = ξ .

2566 CHAPTER 76. IMPLICIT STOCHASTIC EQUATIONS1 T 1/2< | sup (Bun, Un)! (t) ((/ |b, — Bz, ar) JaeQ21€[0,7] 01/2 r 1/2<([, ap omnio) (ff [es -e1%¢r)QtE[0,7] 2/0T 3 1/2<¢([ [ le.—eliar)which converges to 0. &fReturn now to the equation solved by u, in 76.4.37. Apply the Ito formula to this one.This yields for a.e. f,From 76.4.32(Buy (t) , Up ()) = 5 (Buoy, uon) + f (A (0) tnt) ds = 5 [ (Bo,,®,) dsNiet t+ (faunas [ (®,0J7!)* Bun oJdW (76.4.45)0 0Assume without loss of generality that T is not in the exceptional set. If not, consider allT' close to T such that T’ is not in the exceptional set.[ ((AB-+A(@)) Unstn) ds1= 5 (Buon: ton) ~ 5 (Br (T) un (y+ fo (f,Un) dsT x 1 rT T+ (®, oJ!) Bun oddW +5 | (BO,,,)ds+ | (ABun, Un) ds0 0 0Now it follows from 76.4.42 applied to t = T and the above lemma thatTlim sup [| ((AB+A(@))Un,Un) dsT . 1 /T T+f (boJ"') Buosdw+; | (BO,®)ds+ | (ABu,u) ds0 0 0and from 76.4.43, the expression on the right equals fo (ABu+ &,u) ds. HenceT Tlimsup {| ((AB+A(@)) Un, Un) ds < | (ABu+6,u) ds0noo J0)Then since AB + A(@) is monotone and hemicontinuous, it is type M and so this requiresA(@)u=6.