Metamath Proof Explorer


Theorem zringlpirlem1

Description: Lemma for zringlpir . A nonzero ideal of integers contains some positive integers. (Contributed by Stefan O'Rear, 3-Jan-2015) (Revised by AV, 9-Jun-2019)

Ref Expression
Hypotheses zringlpirlem.i
|- ( ph -> I e. ( LIdeal ` ZZring ) )
zringlpirlem.n0
|- ( ph -> I =/= { 0 } )
Assertion zringlpirlem1
|- ( ph -> ( I i^i NN ) =/= (/) )

Proof

Step Hyp Ref Expression
1 zringlpirlem.i
 |-  ( ph -> I e. ( LIdeal ` ZZring ) )
2 zringlpirlem.n0
 |-  ( ph -> I =/= { 0 } )
3 simplr
 |-  ( ( ( ph /\ a e. I ) /\ a =/= 0 ) -> a e. I )
4 eleq1
 |-  ( ( abs ` a ) = a -> ( ( abs ` a ) e. I <-> a e. I ) )
5 3 4 syl5ibrcom
 |-  ( ( ( ph /\ a e. I ) /\ a =/= 0 ) -> ( ( abs ` a ) = a -> ( abs ` a ) e. I ) )
6 zsubrg
 |-  ZZ e. ( SubRing ` CCfld )
7 subrgsubg
 |-  ( ZZ e. ( SubRing ` CCfld ) -> ZZ e. ( SubGrp ` CCfld ) )
8 6 7 ax-mp
 |-  ZZ e. ( SubGrp ` CCfld )
9 zringbas
 |-  ZZ = ( Base ` ZZring )
10 eqid
 |-  ( LIdeal ` ZZring ) = ( LIdeal ` ZZring )
11 9 10 lidlss
 |-  ( I e. ( LIdeal ` ZZring ) -> I C_ ZZ )
12 1 11 syl
 |-  ( ph -> I C_ ZZ )
13 12 sselda
 |-  ( ( ph /\ a e. I ) -> a e. ZZ )
14 df-zring
 |-  ZZring = ( CCfld |`s ZZ )
15 eqid
 |-  ( invg ` CCfld ) = ( invg ` CCfld )
16 eqid
 |-  ( invg ` ZZring ) = ( invg ` ZZring )
17 14 15 16 subginv
 |-  ( ( ZZ e. ( SubGrp ` CCfld ) /\ a e. ZZ ) -> ( ( invg ` CCfld ) ` a ) = ( ( invg ` ZZring ) ` a ) )
18 8 13 17 sylancr
 |-  ( ( ph /\ a e. I ) -> ( ( invg ` CCfld ) ` a ) = ( ( invg ` ZZring ) ` a ) )
19 13 zcnd
 |-  ( ( ph /\ a e. I ) -> a e. CC )
20 cnfldneg
 |-  ( a e. CC -> ( ( invg ` CCfld ) ` a ) = -u a )
21 19 20 syl
 |-  ( ( ph /\ a e. I ) -> ( ( invg ` CCfld ) ` a ) = -u a )
22 18 21 eqtr3d
 |-  ( ( ph /\ a e. I ) -> ( ( invg ` ZZring ) ` a ) = -u a )
23 zringring
 |-  ZZring e. Ring
24 1 adantr
 |-  ( ( ph /\ a e. I ) -> I e. ( LIdeal ` ZZring ) )
25 simpr
 |-  ( ( ph /\ a e. I ) -> a e. I )
26 10 16 lidlnegcl
 |-  ( ( ZZring e. Ring /\ I e. ( LIdeal ` ZZring ) /\ a e. I ) -> ( ( invg ` ZZring ) ` a ) e. I )
27 23 24 25 26 mp3an2i
 |-  ( ( ph /\ a e. I ) -> ( ( invg ` ZZring ) ` a ) e. I )
28 22 27 eqeltrrd
 |-  ( ( ph /\ a e. I ) -> -u a e. I )
29 28 adantr
 |-  ( ( ( ph /\ a e. I ) /\ a =/= 0 ) -> -u a e. I )
30 eleq1
 |-  ( ( abs ` a ) = -u a -> ( ( abs ` a ) e. I <-> -u a e. I ) )
31 29 30 syl5ibrcom
 |-  ( ( ( ph /\ a e. I ) /\ a =/= 0 ) -> ( ( abs ` a ) = -u a -> ( abs ` a ) e. I ) )
32 13 zred
 |-  ( ( ph /\ a e. I ) -> a e. RR )
33 32 absord
 |-  ( ( ph /\ a e. I ) -> ( ( abs ` a ) = a \/ ( abs ` a ) = -u a ) )
34 33 adantr
 |-  ( ( ( ph /\ a e. I ) /\ a =/= 0 ) -> ( ( abs ` a ) = a \/ ( abs ` a ) = -u a ) )
35 5 31 34 mpjaod
 |-  ( ( ( ph /\ a e. I ) /\ a =/= 0 ) -> ( abs ` a ) e. I )
36 nnabscl
 |-  ( ( a e. ZZ /\ a =/= 0 ) -> ( abs ` a ) e. NN )
37 13 36 sylan
 |-  ( ( ( ph /\ a e. I ) /\ a =/= 0 ) -> ( abs ` a ) e. NN )
38 35 37 elind
 |-  ( ( ( ph /\ a e. I ) /\ a =/= 0 ) -> ( abs ` a ) e. ( I i^i NN ) )
39 38 ne0d
 |-  ( ( ( ph /\ a e. I ) /\ a =/= 0 ) -> ( I i^i NN ) =/= (/) )
40 zring0
 |-  0 = ( 0g ` ZZring )
41 10 40 lidlnz
 |-  ( ( ZZring e. Ring /\ I e. ( LIdeal ` ZZring ) /\ I =/= { 0 } ) -> E. a e. I a =/= 0 )
42 23 1 2 41 mp3an2i
 |-  ( ph -> E. a e. I a =/= 0 )
43 39 42 r19.29a
 |-  ( ph -> ( I i^i NN ) =/= (/) )