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Theorem trilpo 16411
Description: Real number trichotomy implies the Limited Principle of Omniscience (LPO). We expect that we'd need some form of countable choice to prove the converse.

Here's the outline of the proof. Given an infinite sequence F of zeroes and ones, we need to show the sequence contains a zero or it is all ones. Construct a real number A whose representation in base two consists of a zero, a decimal point, and then the numbers of the sequence. Compare it with one using trichotomy. The three cases from trichotomy are trilpolemlt1 16409 (which means the sequence contains a zero), trilpolemeq1 16408 (which means the sequence is all ones), and trilpolemgt1 16407 (which is not possible).

Equivalent ways to state real number trichotomy (sometimes called "analytic LPO") include decidability of real number apartness (see triap 16397) or that the real numbers are a discrete field (see trirec0 16412).

LPO is known to not be provable in IZF (and most constructive foundations), so this theorem establishes that we will be unable to prove an analogue to qtri3or 10460 for real numbers. (Contributed by Jim Kingdon, 23-Aug-2023.)

Assertion
Ref Expression
trilpo  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  om  e. Omni )
Distinct variable group:    x, y

Proof of Theorem trilpo
Dummy variables  f  i  j  z are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 elmapi 6817 . . . . . 6  |-  ( f  e.  ( { 0 ,  1 }  ^m  NN )  ->  f : NN --> { 0 ,  1 } )
21adantl 277 . . . . 5  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  f : NN --> { 0 ,  1 } )
3 oveq2 6009 . . . . . . . 8  |-  ( i  =  j  ->  (
2 ^ i )  =  ( 2 ^ j ) )
43oveq2d 6017 . . . . . . 7  |-  ( i  =  j  ->  (
1  /  ( 2 ^ i ) )  =  ( 1  / 
( 2 ^ j
) ) )
5 fveq2 5627 . . . . . . 7  |-  ( i  =  j  ->  (
f `  i )  =  ( f `  j ) )
64, 5oveq12d 6019 . . . . . 6  |-  ( i  =  j  ->  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  ( ( 1  /  ( 2 ^ j ) )  x.  ( f `  j
) ) )
76cbvsumv 11872 . . . . 5  |-  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  =  sum_ j  e.  NN  (
( 1  /  (
2 ^ j ) )  x.  ( f `
 j ) )
82, 7trilpolemcl 16405 . . . . . 6  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  e.  RR )
9 1red 8161 . . . . . 6  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  1  e.  RR )
10 simpl 109 . . . . . 6  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x ) )
11 breq1 4086 . . . . . . . 8  |-  ( x  =  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  ->  ( x  <  y  <->  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  <  y )
)
12 eqeq1 2236 . . . . . . . 8  |-  ( x  =  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  ->  ( x  =  y  <->  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  =  y ) )
13 breq2 4087 . . . . . . . 8  |-  ( x  =  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  ->  ( y  <  x  <->  y  <  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) ) ) )
1411, 12, 133orbi123d 1345 . . . . . . 7  |-  ( x  =  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  ->  ( (
x  <  y  \/  x  =  y  \/  y  <  x )  <->  ( sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  <  y  \/  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  y  \/  y  <  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
) ) ) )
15 breq2 4087 . . . . . . . 8  |-  ( y  =  1  ->  ( sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  <  y  <->  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  <  1
) )
16 eqeq2 2239 . . . . . . . 8  |-  ( y  =  1  ->  ( sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  y  <->  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  =  1 ) )
17 breq1 4086 . . . . . . . 8  |-  ( y  =  1  ->  (
y  <  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  <->  1  <  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) ) ) )
1815, 16, 173orbi123d 1345 . . . . . . 7  |-  ( y  =  1  ->  (
( sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  <  y  \/  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  y  \/  y  <  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
) )  <->  ( sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  <  1  \/  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  1  \/  1  <  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
) ) ) )
1914, 18rspc2va 2921 . . . . . 6  |-  ( ( ( sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  e.  RR  /\  1  e.  RR )  /\  A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x ) )  ->  ( sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  <  1  \/  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  =  1  \/  1  <  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) ) ) )
208, 9, 10, 19syl21anc 1270 . . . . 5  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  ( sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  <  1  \/  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  =  1  \/  1  <  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) ) ) )
212, 7, 20trilpolemres 16410 . . . 4  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  ( E. z  e.  NN  ( f `  z )  =  0  \/  A. z  e.  NN  ( f `  z )  =  1 ) )
2221ralrimiva 2603 . . 3  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  A. f  e.  ( { 0 ,  1 }  ^m  NN ) ( E. z  e.  NN  ( f `  z )  =  0  \/  A. z  e.  NN  ( f `  z )  =  1 ) )
23 nnex 9116 . . . 4  |-  NN  e.  _V
24 isomninn 16399 . . . 4  |-  ( NN  e.  _V  ->  ( NN  e. Omni 
<-> 
A. f  e.  ( { 0 ,  1 }  ^m  NN ) ( E. z  e.  NN  ( f `  z )  =  0  \/  A. z  e.  NN  ( f `  z )  =  1 ) ) )
2523, 24ax-mp 5 . . 3  |-  ( NN  e. Omni 
<-> 
A. f  e.  ( { 0 ,  1 }  ^m  NN ) ( E. z  e.  NN  ( f `  z )  =  0  \/  A. z  e.  NN  ( f `  z )  =  1 ) )
2622, 25sylibr 134 . 2  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  NN  e. Omni )
27 nnenom 10656 . . 3  |-  NN  ~~  om
28 enomni 7306 . . 3  |-  ( NN 
~~  om  ->  ( NN  e. Omni 
<->  om  e. Omni ) )
2927, 28ax-mp 5 . 2  |-  ( NN  e. Omni 
<->  om  e. Omni )
3026, 29sylib 122 1  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  om  e. Omni )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    <-> wb 105    \/ wo 713    \/ w3o 1001    = wceq 1395    e. wcel 2200   A.wral 2508   E.wrex 2509   _Vcvv 2799   {cpr 3667   class class class wbr 4083   omcom 4682   -->wf 5314   ` cfv 5318  (class class class)co 6001    ^m cmap 6795    ~~ cen 6885  Omnicomni 7301   RRcr 7998   0cc0 7999   1c1 8000    x. cmul 8004    < clt 8181    / cdiv 8819   NNcn 9110   2c2 9161   ^cexp 10760   sum_csu 11864
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-coll 4199  ax-sep 4202  ax-nul 4210  ax-pow 4258  ax-pr 4293  ax-un 4524  ax-setind 4629  ax-iinf 4680  ax-cnex 8090  ax-resscn 8091  ax-1cn 8092  ax-1re 8093  ax-icn 8094  ax-addcl 8095  ax-addrcl 8096  ax-mulcl 8097  ax-mulrcl 8098  ax-addcom 8099  ax-mulcom 8100  ax-addass 8101  ax-mulass 8102  ax-distr 8103  ax-i2m1 8104  ax-0lt1 8105  ax-1rid 8106  ax-0id 8107  ax-rnegex 8108  ax-precex 8109  ax-cnre 8110  ax-pre-ltirr 8111  ax-pre-ltwlin 8112  ax-pre-lttrn 8113  ax-pre-apti 8114  ax-pre-ltadd 8115  ax-pre-mulgt0 8116  ax-pre-mulext 8117  ax-arch 8118  ax-caucvg 8119
This theorem depends on definitions:  df-bi 117  df-dc 840  df-3or 1003  df-3an 1004  df-tru 1398  df-fal 1401  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ne 2401  df-nel 2496  df-ral 2513  df-rex 2514  df-reu 2515  df-rmo 2516  df-rab 2517  df-v 2801  df-sbc 3029  df-csb 3125  df-dif 3199  df-un 3201  df-in 3203  df-ss 3210  df-nul 3492  df-if 3603  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-uni 3889  df-int 3924  df-iun 3967  df-br 4084  df-opab 4146  df-mpt 4147  df-tr 4183  df-id 4384  df-po 4387  df-iso 4388  df-iord 4457  df-on 4459  df-ilim 4460  df-suc 4462  df-iom 4683  df-xp 4725  df-rel 4726  df-cnv 4727  df-co 4728  df-dm 4729  df-rn 4730  df-res 4731  df-ima 4732  df-iota 5278  df-fun 5320  df-fn 5321  df-f 5322  df-f1 5323  df-fo 5324  df-f1o 5325  df-fv 5326  df-isom 5327  df-riota 5954  df-ov 6004  df-oprab 6005  df-mpo 6006  df-1st 6286  df-2nd 6287  df-recs 6451  df-irdg 6516  df-frec 6537  df-1o 6562  df-2o 6563  df-oadd 6566  df-er 6680  df-map 6797  df-en 6888  df-dom 6889  df-fin 6890  df-omni 7302  df-pnf 8183  df-mnf 8184  df-xr 8185  df-ltxr 8186  df-le 8187  df-sub 8319  df-neg 8320  df-reap 8722  df-ap 8729  df-div 8820  df-inn 9111  df-2 9169  df-3 9170  df-4 9171  df-n0 9370  df-z 9447  df-uz 9723  df-q 9815  df-rp 9850  df-ico 10090  df-fz 10205  df-fzo 10339  df-seqfrec 10670  df-exp 10761  df-ihash 10998  df-cj 11353  df-re 11354  df-im 11355  df-rsqrt 11509  df-abs 11510  df-clim 11790  df-sumdc 11865
This theorem is referenced by: (None)
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