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Theorem nmcopexlem1 9889
Description: Lemma for nmcopex 9895 (Theorem 3.5(i) of [Beran] p. 99). A sufficient condition for the norm of an operator to be real, based on its definition and the properties of supremum. Compared to Beran, we use a direct proof instead of a proof by contradiction.
Hypotheses
Ref Expression
nmcopex.1 |- T e. LinOp
nmcopex.2 |- T e. ConOp
Assertion
Ref Expression
nmcopexlem1 |- ((n e. NN /\ A.x e. H~ ((normh` x) <_ 1 -> -. n < (normh` (T` x)))) -> (normop` T) e. RR)
Distinct variable group:   x,T,n

Proof of Theorem nmcopexlem1
StepHypRef Expression
1 ra4 1691 . . . . . . . . 9 |- (A.n e. RR E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y -> (n e. RR -> E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y))
21impcom 351 . . . . . . . 8 |- ((n e. RR /\ A.n e. RR E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y) -> E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y)
3 nnret 5885 . . . . . . . 8 |- (n e. NN -> n e. RR)
4 nmcopex.1 . . . . . . . . . . . . 13 |- T e. LinOp
54lnopf 9832 . . . . . . . . . . . 12 |- T:H~-->H~
6 nmopsetretHIL 9731 . . . . . . . . . . . 12 |- (T:H~-->H~ -> {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} (_ RR)
75, 6ax-mp 7 . . . . . . . . . . 11 |- {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} (_ RR
8 ressxr 5478 . . . . . . . . . . 11 |- RR (_ RR*
97, 8sstri 2069 . . . . . . . . . 10 |- {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} (_ RR*
10 supxrunb2 6045 . . . . . . . . . . 11 |- ({z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} (_ RR* -> (A.n e. RR E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y <-> sup({z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}, RR*, < ) = +oo))
11 nmopvalt 9722 . . . . . . . . . . . . 13 |- (T:H~-->H~ -> (normop` T) = sup({z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}, RR*, < ))
125, 11ax-mp 7 . . . . . . . . . . . 12 |- (normop` T) = sup({z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}, RR*, < )
1312eqeq1i 1479 . . . . . . . . . . 11 |- ((normop` T) = +oo <-> sup({z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}, RR*, < ) = +oo)
1410, 13syl6rbbr 538 . . . . . . . . . 10 |- ({z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} (_ RR* -> ((normop` T) = +oo <-> A.n e. RR E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y))
159, 14ax-mp 7 . . . . . . . . 9 |- ((normop` T) = +oo <-> A.n e. RR E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y)
1615biimp 151 . . . . . . . 8 |- ((normop` T) = +oo -> A.n e. RR E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y)
172, 3, 16syl2an 454 . . . . . . 7 |- ((n e. NN /\ (normop` T) = +oo) -> E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y)
18 rexcom4 1820 . . . . . . . . 9 |- (E.x e. H~ E.y(((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y) <-> E.yE.x e. H~ (((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y))
19 19.42v 1306 . . . . . . . . . . 11 |- (E.y((normh` x) <_ 1 /\ (y = (normh` (T` x)) /\ n < y)) <-> ((normh` x) <_ 1 /\ E.y(y = (normh` (T` x)) /\ n < y)))
20 anass 439 . . . . . . . . . . . . 13 |- ((((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y) <-> ((normh` x) <_ 1 /\ (y = (normh` (T` x)) /\ n < y)))
2120bicomi 172 . . . . . . . . . . . 12 |- (((normh` x) <_ 1 /\ (y = (normh` (T` x)) /\ n < y)) <-> (((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y))
2221exbii 1049 . . . . . . . . . . 11 |- (E.y((normh` x) <_ 1 /\ (y = (normh` (T` x)) /\ n < y)) <-> E.y(((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y))
23 fvex 3723 . . . . . . . . . . . . 13 |- (normh` (T` x)) e. V
24 breq2 2618 . . . . . . . . . . . . 13 |- (y = (normh` (T` x)) -> (n < y <-> n < (normh` (T` x))))
2523, 24ceqsexv 1831 . . . . . . . . . . . 12 |- (E.y(y = (normh` (T` x)) /\ n < y) <-> n < (normh` (T` x)))
2625anbi2i 480 . . . . . . . . . . 11 |- (((normh` x) <_ 1 /\ E.y(y = (normh` (T` x)) /\ n < y)) <-> ((normh` x) <_ 1 /\ n < (normh` (T` x))))
2719, 22, 263bitr3r 182 . . . . . . . . . 10 |- (((normh` x) <_ 1 /\ n < (normh` (T` x))) <-> E.y(((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y))
2827rexbii 1665 . . . . . . . . 9 |- (E.x e. H~ ((normh` x) <_ 1 /\ n < (normh` (T` x))) <-> E.x e. H~ E.y(((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y))
29 visset 1809 . . . . . . . . . . . . 13 |- y e. V
30 eqeq1 1478 . . . . . . . . . . . . . . 15 |- (z = y -> (z = (normh` (T` x)) <-> y = (normh` (T` x))))
3130anbi2d 615 . . . . . . . . . . . . . 14 |- (z = y -> (((normh` x) <_ 1 /\ z = (normh` (T` x))) <-> ((normh` x) <_ 1 /\ y = (normh` (T` x)))))
3231rexbidv 1661 . . . . . . . . . . . . 13 |- (z = y -> (E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x))) <-> E.x e. H~ ((normh` x) <_ 1 /\ y = (normh` (T` x)))))
3329, 32elab 1893 . . . . . . . . . . . 12 |- (y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} <-> E.x e. H~ ((normh` x) <_ 1 /\ y = (normh` (T` x))))
3433anbi1i 481 . . . . . . . . . . 11 |- ((y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} /\ n < y) <-> (E.x e. H~ ((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y))
35 r19.41v 1760 . . . . . . . . . . 11 |- (E.x e. H~ (((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y) <-> (E.x e. H~ ((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y))
3634, 35bitr4 176 . . . . . . . . . 10 |- ((y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} /\ n < y) <-> E.x e. H~ (((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y))
3736exbii 1049 . . . . . . . . 9 |- (E.y(y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} /\ n < y) <-> E.yE.x e. H~ (((normh` x) <_ 1 /\ y = (normh` (T` x))) /\ n < y))
3818, 28, 373bitr4 183 . . . . . . . 8 |- (E.x e. H~ ((normh` x) <_ 1 /\ n < (normh` (T` x))) <-> E.y(y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} /\ n < y))
39 df-rex 1647 . . . . . . . 8 |- (E.y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))}n < y <-> E.y(y e. {z | E.x e. H~ ((normh` x) <_ 1 /\ z = (normh` (T` x)))} /\ n < y))
4038, 39bitr4 176 . . . . . . 7 |- (E.x e. H~ ((normh` x) <_ 1 /\ n < (normh` (T`