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Theorem trilpo 14794
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 14792 (which means the sequence contains a zero), trilpolemeq1 14791 (which means the sequence is all ones), and trilpolemgt1 14790 (which is not possible).

Equivalent ways to state real number trichotomy (sometimes called "analytic LPO") include decidability of real number apartness (see triap 14780) or that the real numbers are a discrete field (see trirec0 14795).

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 10243 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 6670 . . . . . 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 5883 . . . . . . . 8  |-  ( i  =  j  ->  (
2 ^ i )  =  ( 2 ^ j ) )
43oveq2d 5891 . . . . . . 7  |-  ( i  =  j  ->  (
1  /  ( 2 ^ i ) )  =  ( 1  / 
( 2 ^ j
) ) )
5 fveq2 5516 . . . . . . 7  |-  ( i  =  j  ->  (
f `  i )  =  ( f `  j ) )
64, 5oveq12d 5893 . . . . . 6  |-  ( i  =  j  ->  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  ( ( 1  /  ( 2 ^ j ) )  x.  ( f `  j
) ) )
76cbvsumv 11369 . . . . 5  |-  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  =  sum_ j  e.  NN  (
( 1  /  (
2 ^ j ) )  x.  ( f `
 j ) )
82, 7trilpolemcl 14788 . . . . . 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 7972 . . . . . 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 4007 . . . . . . . 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 2184 . . . . . . . 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 4008 . . . . . . . 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 1311 . . . . . . 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 4008 . . . . . . . 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 2187 . . . . . . . 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 4007 . . . . . . . 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 1311 . . . . . . 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 2856 . . . . . 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 1237 . . . . 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 14793 . . . 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 2550 . . 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 8925 . . . 4  |-  NN  e.  _V
24 isomninn 14782 . . . 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 10434 . . 3  |-  NN  ~~  om
28 enomni 7137 . . 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 708    \/ w3o 977    = wceq 1353    e. wcel 2148   A.wral 2455   E.wrex 2456   _Vcvv 2738   {cpr 3594   class class class wbr 4004   omcom 4590   -->wf 5213   ` cfv 5217  (class class class)co 5875    ^m cmap 6648    ~~ cen 6738  Omnicomni 7132   RRcr 7810   0cc0 7811   1c1 7812    x. cmul 7816    < clt 7992    / cdiv 8629   NNcn 8919   2c2 8970   ^cexp 10519   sum_csu 11361
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 614  ax-in2 615  ax-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-13 2150  ax-14 2151  ax-ext 2159  ax-coll 4119  ax-sep 4122  ax-nul 4130  ax-pow 4175  ax-pr 4210  ax-un 4434  ax-setind 4537  ax-iinf 4588  ax-cnex 7902  ax-resscn 7903  ax-1cn 7904  ax-1re 7905  ax-icn 7906  ax-addcl 7907  ax-addrcl 7908  ax-mulcl 7909  ax-mulrcl 7910  ax-addcom 7911  ax-mulcom 7912  ax-addass 7913  ax-mulass 7914  ax-distr 7915  ax-i2m1 7916  ax-0lt1 7917  ax-1rid 7918  ax-0id 7919  ax-rnegex 7920  ax-precex 7921  ax-cnre 7922  ax-pre-ltirr 7923  ax-pre-ltwlin 7924  ax-pre-lttrn 7925  ax-pre-apti 7926  ax-pre-ltadd 7927  ax-pre-mulgt0 7928  ax-pre-mulext 7929  ax-arch 7930  ax-caucvg 7931
This theorem depends on definitions:  df-bi 117  df-dc 835  df-3or 979  df-3an 980  df-tru 1356  df-fal 1359  df-nf 1461  df-sb 1763  df-eu 2029  df-mo 2030  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ne 2348  df-nel 2443  df-ral 2460  df-rex 2461  df-reu 2462  df-rmo 2463  df-rab 2464  df-v 2740  df-sbc 2964  df-csb 3059  df-dif 3132  df-un 3134  df-in 3136  df-ss 3143  df-nul 3424  df-if 3536  df-pw 3578  df-sn 3599  df-pr 3600  df-op 3602  df-uni 3811  df-int 3846  df-iun 3889  df-br 4005  df-opab 4066  df-mpt 4067  df-tr 4103  df-id 4294  df-po 4297  df-iso 4298  df-iord 4367  df-on 4369  df-ilim 4370  df-suc 4372  df-iom 4591  df-xp 4633  df-rel 4634  df-cnv 4635  df-co 4636  df-dm 4637  df-rn 4638  df-res 4639  df-ima 4640  df-iota 5179  df-fun 5219  df-fn 5220  df-f 5221  df-f1 5222  df-fo 5223  df-f1o 5224  df-fv 5225  df-isom 5226  df-riota 5831  df-ov 5878  df-oprab 5879  df-mpo 5880  df-1st 6141  df-2nd 6142  df-recs 6306  df-irdg 6371  df-frec 6392  df-1o 6417  df-2o 6418  df-oadd 6421  df-er 6535  df-map 6650  df-en 6741  df-dom 6742  df-fin 6743  df-omni 7133  df-pnf 7994  df-mnf 7995  df-xr 7996  df-ltxr 7997  df-le 7998  df-sub 8130  df-neg 8131  df-reap 8532  df-ap 8539  df-div 8630  df-inn 8920  df-2 8978  df-3 8979  df-4 8980  df-n0 9177  df-z 9254  df-uz 9529  df-q 9620  df-rp 9654  df-ico 9894  df-fz 10009  df-fzo 10143  df-seqfrec 10446  df-exp 10520  df-ihash 10756  df-cj 10851  df-re 10852  df-im 10853  df-rsqrt 11007  df-abs 11008  df-clim 11287  df-sumdc 11362
This theorem is referenced by: (None)
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